From 50691212bcebaf1e540fe0371b61be199e4ad761 Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sun, 7 Dec 2014 02:56:16 -0500
Subject: [PATCH 1/7] cleanup julia_init options

moves all configuration options into jl_compileropts
compute the abspath/realpath of file paths in the config to avoid issues with chdir
---
 Makefile              |   4 +-
 base/client.jl        |   3 -
 base/sysimg.jl        |   2 +
 src/codegen.cpp       |   2 +-
 src/dlload.c          |   2 +-
 src/dump.c            |  18 +++--
 src/init.c            | 164 ++++++++++++++++++++++++++++++++++--------
 src/jlapi.c           |  38 +++-------
 src/julia.h           |  17 ++---
 src/support/dirpath.h |  11 ++-
 src/support/ios.c     |   2 +-
 src/support/ios.h     |   2 +-
 ui/repl.c             |  61 ++--------------
 13 files changed, 178 insertions(+), 148 deletions(-)

diff --git a/Makefile b/Makefile
index 03d203c8987e7..a905fa679b379 100644
--- a/Makefile
+++ b/Makefile
@@ -300,8 +300,8 @@ else ifeq ($(OS), Linux)
 	done
 endif
 
-	# Overwrite JL_SYSTEM_IMAGE_PATH in julia binaries
-	for julia in $(DESTDIR)$(bindir)/julia* ; do \
+	# Overwrite JL_SYSTEM_IMAGE_PATH in julia library
+	for julia in $(DESTDIR)$(private_libdir)/libjulia*.$(SHLIB_EXT) ; do \
 		$(call spawn,$(build_bindir)/stringreplace $$(strings -t x - $$julia | grep "sys.ji$$" | awk '{print $$1;}' ) "$(private_libdir_rel)/sys.ji" 256 $(call cygpath_w,$$julia)); \
 	done
 endif
diff --git a/base/client.jl b/base/client.jl
index 3518498795e83..e8dc8b0b19009 100644
--- a/base/client.jl
+++ b/base/client.jl
@@ -372,13 +372,10 @@ import .Terminals
 import .REPL
 
 function _start()
-    early_init()
-
     try
         init_parallel()
         init_bind_addr(ARGS)
         any(a->(a=="--worker"), ARGS) || init_head_sched()
-        init_load_path()
         (quiet,repl,startup,color_set,no_history_file) = process_options(copy(ARGS))
 
         local term
diff --git a/base/sysimg.jl b/base/sysimg.jl
index 67aa85ba7dd77..a33c5a37a52e6 100644
--- a/base/sysimg.jl
+++ b/base/sysimg.jl
@@ -294,6 +294,8 @@ function __init__()
     reinit_stdio()
     Multimedia.reinit_displays() # since Multimedia.displays uses STDOUT as fallback
     fdwatcher_init()
+    early_init()
+    init_load_path()
 end
 
 include("precompile.jl")
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 8fb7738559692..69082212b1dbc 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -869,7 +869,7 @@ static void coverageVisitLine(std::string filename, int line)
 
 void write_log_data(logdata_t logData, const char *extension)
 {
-    std::string base = std::string(julia_home);
+    std::string base = std::string(jl_compileropts.julia_home);
     base = base + "/../share/julia/base/";
     logdata_t::iterator it = logData.begin();
     for (; it != logData.end(); it++) {
diff --git a/src/dlload.c b/src/dlload.c
index ef5332696e176..33b6249e34ff2 100644
--- a/src/dlload.c
+++ b/src/dlload.c
@@ -116,7 +116,7 @@ static uv_lib_t *jl_load_dynamic_library_(char *modname, unsigned flags, int thr
                     ext = extensions[i];
                     path[0] = '\0';
                     handle->handle = NULL;
-                    if (dl_path[len-1] == PATHSEP)
+                    if (dl_path[len-1] == PATHSEPSTRING[0])
                         snprintf(path, PATHBUF, "%s%s%s", dl_path, modname, ext);
                     else
                         snprintf(path, PATHBUF, "%s" PATHSEPSTRING "%s%s", dl_path, modname, ext);
diff --git a/src/dump.c b/src/dump.c
index b9ea91b53e8f4..01f0d502ec0f0 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -1305,7 +1305,7 @@ void jl_deserialize_lambdas_from_mod(ios_t *s)
 
 extern jl_array_t *jl_module_init_order;
 
-DLLEXPORT void jl_save_system_image(char *fname)
+DLLEXPORT void jl_save_system_image(const char *fname)
 {
     jl_gc_collect();
     jl_gc_collect();
@@ -1339,8 +1339,8 @@ DLLEXPORT void jl_save_system_image(char *fname)
         for(i=0; i < jl_array_len(jl_module_init_order); i++) {
             // NULL out any modules that weren't saved
             jl_value_t *mod = jl_cellref(jl_module_init_order, i);
-            if (ptrhash_get(&backref_table, mod) == HT_NOTFOUND)
-                jl_cellset(jl_module_init_order, i, NULL);
+            (void)mod;
+            assert(ptrhash_get(&backref_table, mod) != HT_NOTFOUND);
         }
     }
     jl_serialize_value(&f, jl_module_init_order);
@@ -1360,11 +1360,10 @@ extern void jl_get_system_hooks(void);
 extern void jl_get_uv_hooks();
 
 DLLEXPORT
-void jl_restore_system_image(char *fname)
+void jl_restore_system_image(const char *fname)
 {
     ios_t f;
-    char *fpath = fname;
-    if (ios_file(&f, fpath, 1, 0, 0, 0) == NULL) {
+    if (ios_file(&f, fname, 1, 0, 0, 0) == NULL) {
         JL_PRINTF(JL_STDERR, "System image file \"%s\" not found\n", fname);
         exit(1);
     }
@@ -1432,14 +1431,13 @@ void jl_restore_system_image(char *fname)
     //ios_printf(ios_stderr, "backref_list.len = %d\n", backref_list.len);
     arraylist_free(&backref_list);
     ios_close(&f);
-    if (fpath != fname) free(fpath);
 
 #ifdef JL_GC_MARKSWEEP
     if (en) jl_gc_enable();
 #endif
     // restore the value of our "magic" JULIA_HOME variable/constant
     jl_get_binding_wr(jl_core_module, jl_symbol("JULIA_HOME"))->value =
-        jl_cstr_to_string(julia_home);
+        jl_cstr_to_string(jl_compileropts.julia_home);
     mode = last_mode;
     jl_update_all_fptrs();
 }
@@ -1543,7 +1541,7 @@ jl_value_t *jl_uncompress_ast(jl_lambda_info_t *li, jl_value_t *data)
 }
 
 DLLEXPORT
-int jl_save_new_module(char *fname, jl_module_t *mod)
+int jl_save_new_module(const char *fname, jl_module_t *mod)
 {
     ios_t f;
     if (ios_file(&f, fname, 1, 1, 1, 1) == NULL) {
@@ -1583,7 +1581,7 @@ jl_function_t *jl_method_cache_insert(jl_methtable_t *mt, jl_tuple_t *type,
                                       jl_function_t *method);
 
 DLLEXPORT
-jl_module_t *jl_restore_new_module(char *fname)
+jl_module_t *jl_restore_new_module(const char *fname)
 {
     ios_t f;
     if (ios_file(&f, fname, 1, 0, 0, 0) == NULL) {
diff --git a/src/init.c b/src/init.c
index 9519582e2c661..55b2709a9d1a9 100644
--- a/src/init.c
+++ b/src/init.c
@@ -6,6 +6,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <stdio.h>
 #include <setjmp.h>
 #include <assert.h>
 
@@ -42,6 +43,12 @@
 extern "C" {
 #endif
 
+#ifdef _MSC_VER
+DLLEXPORT char * dirname(char *);
+#else
+#include <libgen.h>
+#endif
+
 #ifdef _OS_WINDOWS_
 #define WIN32_LEAN_AND_MEAN
 // Copied from MINGW_FLOAT_H which may not be found due to a collision with the builtin gcc float.h
@@ -78,8 +85,11 @@ DLLEXPORT void jlbacktrace();
 DLLEXPORT void gdbbacktrace();
 DLLEXPORT void gdblookup(ptrint_t ip);
 
-char *julia_home = NULL;
-jl_compileropts_t jl_compileropts = { NULL, // build_path
+static const char system_image_path[256] = JL_SYSTEM_IMAGE_PATH;
+
+jl_compileropts_t jl_compileropts = { NULL, // julia_home
+                                      NULL, // build_path
+                                      system_image_path, // image_file
                                       0,    // code_coverage
                                       0,    // malloc_log
                                       JL_COMPILEROPT_CHECK_BOUNDS_DEFAULT,
@@ -729,10 +739,106 @@ kern_return_t catch_exception_raise(mach_port_t            exception_port,
 
 #endif
 
-void julia_init(char *imageFile)
+static char *abspath(const char *in)
+{ // compute an absolute path location, so that chdir doesn't change the file reference
+#ifndef _OS_WINDOWS_
+    char *out = realpath(in, NULL);
+    if (!out) {
+        if (in[0] == PATHSEPSTRING[0]) {
+            out = strdup(in);
+        }
+        else {
+            size_t path_size = PATH_MAX;
+            size_t len = strlen(in);
+            char *path = (char*)malloc(PATH_MAX);
+            if (uv_cwd(path, &path_size)) {
+                ios_printf(ios_stderr, "fatal error: unexpected error while retrieving current working directory\n");
+                exit(1);
+            }
+            if (path_size + len + 1 >= PATH_MAX) {
+                ios_printf(ios_stderr, "fatal error: current working directory path too long\n");
+                exit(1);
+            }
+            path[path_size-1] = PATHSEPSTRING[0];
+            memcpy(path+path_size, in, len+1);
+            out = strdup(path);
+        }
+    }
+#else
+    DWORD n = GetFullPathName(in, 0, NULL, C_NULL);
+    if (n <= 0) {
+        ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long or GetFullPathName failed\n");
+        exit(1);
+    }
+    char *out = (char*)malloc(n);
+    DWORD m = GetFullPathName(in, n, out, C_NULL);
+    if (n != m + 1) {
+        ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long or GetFullPathName failed\n");
+        exit(1);
+    }
+#endif
+    return out;
+}
+
+static void jl_resolve_sysimg_location()
+{ // note: if you care about lost memory, you should compare the
+  // pointers in jl_compileropts before and after calling julia_init()
+  // and call the appropriate free function on the originals for any that changed
+    char *free_path = NULL;
+    if (!jl_compileropts.julia_home) {
+        jl_compileropts.julia_home = getenv("JULIA_HOME");
+        if (!jl_compileropts.julia_home) {
+            size_t path_size = PATH_MAX;
+            char *path = (char*)malloc(PATH_MAX);
+            if (uv_exepath(path, &path_size)) {
+                ios_printf(ios_stderr, "fatal error: unexpected error while retrieving exepath\n");
+                exit(1);
+            }
+            if (path_size >= PATH_MAX) {
+                ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
+                exit(1);
+            }
+            free_path = path;
+            jl_compileropts.julia_home = dirname(path);
+        }
+    }
+    if (jl_compileropts.julia_home)
+        jl_compileropts.julia_home = abspath(jl_compileropts.julia_home);
+    if (free_path) {
+        free(free_path);
+        free_path = NULL;
+    }
+    if (jl_compileropts.image_file) {
+        if (jl_compileropts.image_file[0] != PATHSEPSTRING[0]) {
+            if (jl_compileropts.image_file == system_image_path) {
+                // build time path, relative to JULIA_HOME
+                char *path = (char*)malloc(PATH_MAX);
+                int n = snprintf(path, PATH_MAX, "%s" PATHSEPSTRING "%s",
+                         jl_compileropts.julia_home, jl_compileropts.image_file);
+                if (n >= PATH_MAX || n < 0) {
+                    ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
+                    exit(1);
+                }
+                free_path = path;
+                jl_compileropts.image_file = path;
+            }
+        }
+    }
+    if (jl_compileropts.image_file)
+        jl_compileropts.image_file = abspath(jl_compileropts.image_file);
+    if (free_path) {
+        free(free_path);
+        free_path = NULL;
+    }
+    if (jl_compileropts.build_path)
+        jl_compileropts.build_path = abspath(jl_compileropts.build_path);
+}
+
+void julia_init()
 {
     jl_io_loop = uv_default_loop(); // this loop will internal events (spawning process etc.),
                                     // best to call this first, since it also initializes libuv
+    jl_resolve_sysimg_location();
     jl_page_size = jl_getpagesize();
     jl_arr_xtralloc_limit = uv_get_total_memory() / 100;  // Extra allocation limited to 1% of total RAM
     jl_find_stack_bottom();
@@ -755,11 +861,11 @@ void julia_init(char *imageFile)
     if (!DuplicateHandle(GetCurrentProcess(), GetCurrentThread(),
                          GetCurrentProcess(), (PHANDLE)&hMainThread, 0,
                          TRUE, DUPLICATE_SAME_ACCESS)) {
-        JL_PRINTF(JL_STDERR, "WARNING: failed to access handle to main thread\n");
+        ios_printf(ios_stderr, "WARNING: failed to access handle to main thread\n");
     }
     SymSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS | SYMOPT_LOAD_LINES);
     if (!SymInitialize(GetCurrentProcess(), NULL, 1)) {
-        JL_PRINTF(JL_STDERR, "WARNING: failed to initalize stack walk info\n");
+        ios_printf(ios_stderr, "WARNING: failed to initialize stack walk info\n");
     }
     needsSymRefreshModuleList = 0;
     uv_lib_t jl_dbghelp;
@@ -805,7 +911,7 @@ void julia_init(char *imageFile)
 
     jl_init_serializer();
 
-    if (!imageFile) {
+    if (!jl_compileropts.image_file) {
         jl_core_module = jl_new_module(jl_symbol("Core"));
         jl_init_intrinsic_functions();
         jl_init_primitives();
@@ -823,13 +929,13 @@ void julia_init(char *imageFile)
         // Core.JULIA_HOME is a "magic" constant, we set it at runtime here
         // since its value gets excluded from the system image
         jl_set_const(jl_core_module, jl_symbol("JULIA_HOME"),
-                     jl_cstr_to_string(julia_home));
+                     jl_cstr_to_string(jl_compileropts.julia_home));
         jl_module_export(jl_core_module, jl_symbol("JULIA_HOME"));
     }
 
-    if (imageFile) {
+    if (jl_compileropts.image_file) {
         JL_TRY {
-            jl_restore_system_image(imageFile);
+            jl_restore_system_image(jl_compileropts.image_file);
         }
         JL_CATCH {
             JL_PRINTF(JL_STDERR, "error during init:\n");
@@ -863,7 +969,6 @@ void julia_init(char *imageFile)
     jl_current_module = jl_main_module;
     jl_root_task->current_module = jl_current_module;
 
-
 #ifndef _OS_WINDOWS_
     signal_stack = malloc(sig_stack_size);
     struct sigaction actf;
@@ -872,11 +977,11 @@ void julia_init(char *imageFile)
     actf.sa_handler = fpe_handler;
     actf.sa_flags = 0;
     if (sigaction(SIGFPE, &actf, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (signal(SIGPIPE,SIG_IGN) == SIG_ERR) {
-        JL_PRINTF(JL_STDERR, "Couldn't set SIGPIPE\n");
+        JL_PRINTF(JL_STDERR, "fatal error: Couldn't set SIGPIPE\n");
         jl_exit(1);
     }
 #if defined (_OS_DARWIN_)
@@ -909,7 +1014,7 @@ void julia_init(char *imageFile)
     ss.ss_size = sig_stack_size;
     ss.ss_sp = signal_stack;
     if (sigaltstack(&ss, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaltstack: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaltstack: %s\n", strerror(errno));
         jl_exit(1);
     }
 
@@ -919,7 +1024,7 @@ void julia_init(char *imageFile)
     act.sa_sigaction = segv_handler;
     act.sa_flags = SA_ONSTACK | SA_SIGINFO;
     if (sigaction(SIGSEGV, &act, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
 #endif // defined(_OS_DARWIN_)
@@ -929,49 +1034,50 @@ void julia_init(char *imageFile)
     act_die.sa_sigaction = sigdie_handler;
     act_die.sa_flags = SA_SIGINFO;
     if (sigaction(SIGINFO, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGBUS, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGILL, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGTERM, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGABRT, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGQUIT, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGSYS, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
     if (sigaction(SIGPIPE, &act_die, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
 #else // defined(_OS_WINDOWS_)
     if (signal(SIGFPE, (void (__cdecl *)(int))fpe_handler) == SIG_ERR) {
-        JL_PRINTF(JL_STDERR, "Couldn't set SIGFPE\n");
+        JL_PRINTF(JL_STDERR, "fatal error: Couldn't set SIGFPE\n");
         jl_exit(1);
     }
+    SetUnhandledExceptionFilter(exception_handler);
 #endif
 
 #ifdef JL_GC_MARKSWEEP
     jl_gc_enable();
 #endif
 
-    if (imageFile)
+    if (jl_compileropts.image_file)
         jl_init_restored_modules();
 
     jl_install_sigint_handler();
@@ -988,11 +1094,10 @@ DLLEXPORT void jl_install_sigint_handler()
     act.sa_sigaction = sigint_handler;
     act.sa_flags = SA_SIGINFO;
     if (sigaction(SIGINT, &act, NULL) < 0) {
-        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
+        JL_PRINTF(JL_STDERR, "fatal error: sigaction: %s\n", strerror(errno));
         jl_exit(1);
     }
 #endif
-    //printf("sigint installed\n");
 }
 
 extern int asprintf(char **str, const char *fmt, ...);
@@ -1002,20 +1107,17 @@ void jl_compile_all(void);
 
 DLLEXPORT int julia_trampoline(int argc, char **argv, int (*pmain)(int ac,char *av[]))
 {
-#if defined(_OS_WINDOWS_)
-    SetUnhandledExceptionFilter(exception_handler);
-#endif
     unsigned char *p = (unsigned char *)&__stack_chk_guard;
     char a = p[sizeof(__stack_chk_guard)-1];
     char b = p[sizeof(__stack_chk_guard)-2];
     char c = p[0];
-    /* If you have the ability to generate random numbers in your kernel then use them */
+    /* If you have the ability to generate random numbers in your kernel then they should be used here */
     p[sizeof(__stack_chk_guard)-1] = 255;
     p[sizeof(__stack_chk_guard)-2] = '\n';
     p[0] = 0;
     JL_SET_STACK_BASE;
     int ret = pmain(argc, argv);
-    char *build_path = jl_compileropts.build_path;
+    const char *build_path = jl_compileropts.build_path;
     if (build_path) {
         if (jl_compileropts.compile_enabled == JL_COMPILEROPT_COMPILE_ALL)
             jl_compile_all();
diff --git a/src/jlapi.c b/src/jlapi.c
index a3eb39b7e0000..f3d94b2d2bc6b 100644
--- a/src/jlapi.c
+++ b/src/jlapi.c
@@ -22,24 +22,6 @@ DLLEXPORT char * __cdecl basename(char *);
 #include <libgen.h>
 #endif
 
-DLLEXPORT char *jl_locate_sysimg(char *jlhome, char *imgpath)
-{
-    if (jlhome == NULL) {
-        char *julia_path = (char*)malloc(512);
-        size_t path_size = 512;
-        uv_exepath(julia_path, &path_size);
-        julia_home = strdup(dirname(julia_path));
-        free(julia_path);
-    }
-    else {
-        julia_home = jlhome;
-    }
-    char path[512];
-    snprintf(path, sizeof(path), "%s%s%s",
-             julia_home, PATHSEPSTRING, imgpath);
-    return strdup(path);
-}
-
 DLLEXPORT void *jl_eval_string(char *str);
 
 int jl_is_initialized(void) { return jl_main_module!=NULL; }
@@ -54,22 +36,22 @@ DLLEXPORT void jl_init_with_image(char *julia_home_dir, char *image_relative_pat
 {
     if (jl_is_initialized()) return;
     libsupport_init();
-    if (image_relative_path == NULL)
-        image_relative_path = JL_SYSTEM_IMAGE_PATH;
-    char *image_file = jl_locate_sysimg(julia_home_dir, image_relative_path);
-    julia_init(image_file);
-    jl_set_const(jl_core_module, jl_symbol("JULIA_HOME"),
-                 jl_cstr_to_string(julia_home));
-    jl_module_export(jl_core_module, jl_symbol("JULIA_HOME"));
-    jl_eval_string("Base.early_init()");
+    jl_compileropts.julia_home = julia_home_dir;
+    if (image_relative_path != NULL)
+        jl_compileropts.image_file = image_relative_path;
+    julia_init();
+    //TODO: these should be part of Multi.__init__()
+    //currently, we have them here since we may not want them
+    //getting unconditionally set from Base.__init__()
+    jl_eval_string("Base.init_parallel()");
+    jl_eval_string("Base.init_bind_addr(ARGS)");
     jl_eval_string("Base.init_head_sched()");
-    jl_eval_string("Base.init_load_path()");
     jl_exception_clear();
 }
 
 DLLEXPORT void jl_init(char *julia_home_dir)
 {
-    jl_init_with_image(julia_home_dir, JL_SYSTEM_IMAGE_PATH);
+    jl_init_with_image(julia_home_dir, NULL);
 }
 
 DLLEXPORT void *jl_eval_string(char *str)
diff --git a/src/julia.h b/src/julia.h
index 277f0685cd877..f0432ffba4f3e 100644
--- a/src/julia.h
+++ b/src/julia.h
@@ -856,17 +856,16 @@ DLLEXPORT void jl_exception_clear(void);
     }
 
 // initialization functions
-DLLEXPORT void julia_init(char *imageFile);
-DLLEXPORT int julia_trampoline(int argc, char *argv[], int (*pmain)(int ac,char *av[]));
+DLLEXPORT void julia_init();
 DLLEXPORT void jl_init(char *julia_home_dir);
 DLLEXPORT void jl_init_with_image(char *julia_home_dir, char *image_relative_path);
 DLLEXPORT int jl_is_initialized(void);
-DLLEXPORT extern char *julia_home;
+DLLEXPORT int julia_trampoline(int argc, char *argv[], int (*pmain)(int ac,char *av[]));
 
-DLLEXPORT void jl_save_system_image(char *fname);
-DLLEXPORT void jl_restore_system_image(char *fname);
-DLLEXPORT int jl_save_new_module(char *fname, jl_module_t *mod);
-DLLEXPORT jl_module_t *jl_restore_new_module(char *fname);
+DLLEXPORT void jl_save_system_image(const char *fname);
+DLLEXPORT void jl_restore_system_image(const char *fname);
+DLLEXPORT int jl_save_new_module(const char *fname, jl_module_t *mod);
+DLLEXPORT jl_module_t *jl_restore_new_module(const char *fname);
 void jl_init_restored_modules();
 
 // front end interface
@@ -1328,7 +1327,9 @@ void show_execution_point(char *filename, int lno);
 // compiler options -----------------------------------------------------------
 
 typedef struct {
-    char *build_path;
+    const char *julia_home;
+    const char *build_path;
+    const char *image_file;
     int8_t code_coverage;
     int8_t malloc_log;
     int8_t check_bounds;
diff --git a/src/support/dirpath.h b/src/support/dirpath.h
index 6cfd965ea0ea8..28fff4ab96def 100644
--- a/src/support/dirpath.h
+++ b/src/support/dirpath.h
@@ -2,18 +2,15 @@
 #define DIRPATH_H
 
 #ifdef _OS_WINDOWS_
-#define PATHSEP '\\'
 #define PATHSEPSTRING "\\"
-#define PATHLISTSEP ';'
 #define PATHLISTSEPSTRING ";"
-#define ISPATHSEP(c) ((c)=='/' || (c)=='\\')
-#define MAXPATHLEN 1024
+#ifdef _MSC_VER
+#define PATH_MAX MAX_PATH
+#endif
 #else
-#define PATHSEP '/'
 #define PATHSEPSTRING "/"
-#define PATHLISTSEP ':'
 #define PATHLISTSEPSTRING ":"
-#define ISPATHSEP(c) ((c)=='/')
+#define PATH_MAX 1024
 #endif
 
 #endif
diff --git a/src/support/ios.c b/src/support/ios.c
index dbab4edbca747..d8bd66c7ede4f 100644
--- a/src/support/ios.c
+++ b/src/support/ios.c
@@ -836,7 +836,7 @@ static void _ios_init(ios_t *s)
 
 /* stream object initializers. we do no allocation. */
 
-ios_t *ios_file(ios_t *s, char *fname, int rd, int wr, int create, int trunc)
+ios_t *ios_file(ios_t *s, const char *fname, int rd, int wr, int create, int trunc)
 {
     int flags;
     int fd;
diff --git a/src/support/ios.h b/src/support/ios.h
index d5a72fcc79da5..78c6518df92f1 100644
--- a/src/support/ios.h
+++ b/src/support/ios.h
@@ -100,7 +100,7 @@ DLLEXPORT size_t ios_readprep(ios_t *from, size_t n);
 
 /* stream creation */
 DLLEXPORT
-ios_t *ios_file(ios_t *s, char *fname, int rd, int wr, int create, int trunc);
+ios_t *ios_file(ios_t *s, const char *fname, int rd, int wr, int create, int trunc);
 DLLEXPORT ios_t *ios_mem(ios_t *s, size_t initsize);
 ios_t *ios_str(ios_t *s, char *str);
 ios_t *ios_static_buffer(ios_t *s, char *buf, size_t sz);
diff --git a/ui/repl.c b/ui/repl.c
index 31634902aacbc..49e68a4bbc162 100644
--- a/ui/repl.c
+++ b/ui/repl.c
@@ -4,7 +4,6 @@
 */
 
 #include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
 #include <stdarg.h>
 #include <setjmp.h>
@@ -20,7 +19,6 @@
 
 #ifndef _MSC_VER
 #include <unistd.h>
-#include <libgen.h>
 #include <getopt.h>
 #else
 #include "getopt.h"
@@ -34,27 +32,14 @@
 #error "JL_SYSTEM_IMAGE_PATH not defined!"
 #endif
 
-#ifdef _MSC_VER
-#define PATH_MAX MAX_PATH
-#endif
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#ifdef _MSC_VER
-DLLEXPORT char * dirname(char *);
-#endif
-
-extern DLLEXPORT char *julia_home;
-
-char system_image[256] = JL_SYSTEM_IMAGE_PATH;
-
 static int lisp_prompt = 0;
 static int codecov  = JL_LOG_NONE;
 static int malloclog= JL_LOG_NONE;
 static char *program = NULL;
-char *image_file = NULL;
 
 static const char *usage = "julia [options] [program] [args...]\n";
 static const char *opts =
@@ -111,7 +96,6 @@ void parse_opts(int *argcp, char ***argvp)
     int c;
     opterr = 0;
     int imagepathspecified=0;
-    image_file = system_image;
     int skip = 0;
     int lastind = optind;
     while ((c = getopt_long(*argcp,*argvp,shortopts,longopts,0)) != -1) {
@@ -123,19 +107,19 @@ void parse_opts(int *argcp, char ***argvp)
             lastind = optind;
             break;
         case 'H':
-            julia_home = strdup(optarg);
+            jl_compileropts.julia_home = strdup(optarg);
             break;
         case 'b':
             jl_compileropts.build_path = strdup(optarg);
             if (!imagepathspecified)
-                image_file = NULL;
+                jl_compileropts.image_file = NULL;
             break;
         case 'J':
-            image_file = strdup(optarg);
+            jl_compileropts.image_file = strdup(optarg);
             imagepathspecified = 1;
             break;
         case 'h':
-            printf("%s%s", usage, opts);
+            ios_printf(ios_stdout, "%s%s", usage, opts);
             exit(0);
         case 'O':
             jl_compileropts.opt_level = 1;
@@ -206,47 +190,14 @@ void parse_opts(int *argcp, char ***argvp)
     }
     jl_compileropts.code_coverage = codecov;
     jl_compileropts.malloc_log    = malloclog;
-    if (!julia_home) {
-        julia_home = getenv("JULIA_HOME");
-        if (julia_home) {
-            julia_home = strdup(julia_home);
-        }
-        else {
-            char *julia_path = (char*)malloc(PATH_MAX);
-            size_t path_size = PATH_MAX;
-            uv_exepath(julia_path, &path_size);
-            julia_home = strdup(dirname(julia_path));
-            free(julia_path);
-        }
-    }
     optind -= skip;
     *argvp += optind;
     *argcp -= optind;
-    if (image_file==NULL && *argcp > 0) {
+    if (jl_compileropts.image_file==NULL && *argcp > 0) {
         if (strcmp((*argvp)[0], "-")) {
             program = (*argvp)[0];
         }
     }
-    if (image_file) {
-        if (image_file[0] != PATHSEP) {
-            uv_stat_t stbuf;
-            char path[512];
-            if (!imagepathspecified) {
-                // build time path relative to JULIA_HOME
-                snprintf(path, sizeof(path), "%s%s%s",
-                         julia_home, PATHSEPSTRING, system_image);
-                image_file = strdup(path);
-            }
-            else if (jl_stat(image_file, (char*)&stbuf) != 0) {
-                // otherwise try julia_home/../lib/julia/%s
-                snprintf(path, sizeof(path), "%s%s%s",
-                         julia_home,
-                         PATHSEPSTRING ".." PATHSEPSTRING "lib" PATHSEPSTRING "julia" PATHSEPSTRING,
-                         image_file);
-                image_file = strdup(path);
-            }
-        }
-    }
 }
 
 static int exec_program(void)
@@ -384,7 +335,7 @@ int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
         jl_lisp_prompt();
         return 0;
     }
-    julia_init(lisp_prompt ? NULL : image_file);
+    julia_init();
     return julia_trampoline(argc, (char**)argv, true_main);
 }
 

From 54affdb3f37e8d02c9d6e1806229c4933890a094 Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Fri, 12 Dec 2014 22:23:21 -0500
Subject: [PATCH 2/7] simplify initialization / startup / embedded /
 task-switch api

---
 base/boot.jl         |   2 +-
 base/client.jl       |  11 +--
 base/exports.jl      |   1 +
 src/ast.c            |   2 +-
 src/codegen.cpp      |   5 +-
 src/dump.c           |  12 +--
 src/gc.c             |   2 +-
 src/init.c           |  77 ++++++----------
 src/jl_uv.c          |   6 +-
 src/jlapi.c          |  26 +++---
 src/julia.h          |  49 ++++++-----
 src/julia_internal.h |   8 +-
 src/task.c           | 204 ++++++++++++++++++++++++++-----------------
 ui/repl.c            |  13 ++-
 14 files changed, 221 insertions(+), 197 deletions(-)

diff --git a/base/boot.jl b/base/boot.jl
index 0ecec7f2fa14c..8c6f984be0770 100644
--- a/base/boot.jl
+++ b/base/boot.jl
@@ -147,7 +147,7 @@ export
     # method reflection
     applicable, invoke, method_exists,
     # constants
-    JULIA_HOME, nothing, Main,
+    nothing, Main,
     # intrinsics module
     Intrinsics
     #ccall, cglobal, llvmcall, abs_float, add_float, add_int, and_int, ashr_int,
diff --git a/base/client.jl b/base/client.jl
index e8dc8b0b19009..db9de86654d25 100644
--- a/base/client.jl
+++ b/base/client.jl
@@ -356,6 +356,7 @@ function load_machine_file(path::AbstractString)
 end
 
 function early_init()
+    global const JULIA_HOME = ccall(:jl_get_julia_home, Any, ())
     Sys.init_sysinfo()
     if CPU_CORES > 8 && !("OPENBLAS_NUM_THREADS" in keys(ENV)) && !("OMP_NUM_THREADS" in keys(ENV))
         # Prevent openblas from stating to many threads, unless/until specifically requested
@@ -409,19 +410,16 @@ function _start()
                 # note: currently IOStream is used for file STDIN
                 if isa(STDIN,File) || isa(STDIN,IOStream)
                     # reading from a file, behave like include
-                    eval(parse_input_line(readall(STDIN)))
+                    eval(Main,parse_input_line(readall(STDIN)))
                 else
                     # otherwise behave repl-like
                     while !eof(STDIN)
                         eval_user_input(parse_input_line(STDIN), true)
                     end
                 end
-                if have_color
-                    print(color_normal)
-                end
-                quit()
+            else
+                REPL.run_repl(active_repl)
             end
-            REPL.run_repl(active_repl)
         end
     catch err
         display_error(err,catch_backtrace())
@@ -434,7 +432,6 @@ function _start()
         end
         println()
     end
-    ccall(:uv_atexit_hook, Void, ())
 end
 
 const atexit_hooks = []
diff --git a/base/exports.jl b/base/exports.jl
index 9760a55ad1a36..a17935dce9885 100644
--- a/base/exports.jl
+++ b/base/exports.jl
@@ -163,6 +163,7 @@ export
     Inf,
     Inf16,
     Inf32,
+    JULIA_HOME,
     LOAD_PATH,
     MS_ASYNC,
     MS_INVALIDATE,
diff --git a/src/ast.c b/src/ast.c
index f743641d1cf73..544dafd845d28 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -114,7 +114,7 @@ static builtinspec_t julia_flisp_ast_ext[] = {
     { NULL, NULL }
 };
 
-DLLEXPORT void jl_init_frontend(void)
+void jl_init_frontend(void)
 {
     fl_init(4*1024*1024);
     value_t img = cvalue(iostreamtype, sizeof(ios_t));
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 69082212b1dbc..14c6194435d94 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -130,9 +130,8 @@ void __attribute__(()) __stack_chk_fail()
 #endif
 {
     /* put your panic function or similar in here */
-    fprintf(stderr, "warning: stack corruption detected\n");
-    //assert(0 && "stack corruption detected");
-    //abort();
+    fprintf(stderr, "fatal error: stack corruption detected\n");
+    abort(); // end with abort, since the compiler destroyed the stack upon entry to this function
 }
 }
 
diff --git a/src/dump.c b/src/dump.c
index 01f0d502ec0f0..ac511abf1e3d7 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -452,8 +452,6 @@ static void jl_serialize_module(ios_t *s, jl_module_t *m)
     jl_serialize_value(s, m->parent);
     if (ref_only)
         return;
-    // set on every startup; don't save value
-    jl_sym_t *jhsym = jl_symbol("JULIA_HOME");
     size_t i;
     void **table = m->bindings.table;
     for(i=1; i < m->bindings.size; i+=2) {
@@ -461,12 +459,7 @@ static void jl_serialize_module(ios_t *s, jl_module_t *m)
             jl_binding_t *b = (jl_binding_t*)table[i];
             if (b->owner == m || m != jl_main_module) {
                 jl_serialize_value(s, b->name);
-                if (table[i-1] == jhsym && m == jl_core_module) {
-                    jl_serialize_value(s, NULL);
-                }
-                else {
-                    jl_serialize_value(s, b->value);
-                }
+                jl_serialize_value(s, b->value);
                 jl_serialize_value(s, b->type);
                 jl_serialize_value(s, b->owner);
                 write_int8(s, (b->constp<<2) | (b->exportp<<1) | (b->imported));
@@ -1435,9 +1428,6 @@ void jl_restore_system_image(const char *fname)
 #ifdef JL_GC_MARKSWEEP
     if (en) jl_gc_enable();
 #endif
-    // restore the value of our "magic" JULIA_HOME variable/constant
-    jl_get_binding_wr(jl_core_module, jl_symbol("JULIA_HOME"))->value =
-        jl_cstr_to_string(jl_compileropts.julia_home);
     mode = last_mode;
     jl_update_all_fptrs();
 }
diff --git a/src/gc.c b/src/gc.c
index 758e5832ba4ec..2c871d09a6cba 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -712,7 +712,7 @@ static void gc_mark_task(jl_task_t *ta, int d)
             gc_mark_stack(jl_pgcstack, offset, d);
         }
         else {
-            offset = (char *)ta->stkbuf - ((char *)ta->stackbase - ta->ssize);
+            offset = (char *)ta->stkbuf - ((char *)jl_stackbase - ta->ssize);
             gc_mark_stack(ta->gcstack, offset, d);
         }
 #else
diff --git a/src/init.c b/src/init.c
index 55b2709a9d1a9..0010bf484e882 100644
--- a/src/init.c
+++ b/src/init.c
@@ -7,7 +7,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
-#include <setjmp.h>
 #include <assert.h>
 
 #if defined(__linux__) || defined(__APPLE__) || defined(__FreeBSD__)
@@ -88,6 +87,7 @@ DLLEXPORT void gdblookup(ptrint_t ip);
 static const char system_image_path[256] = JL_SYSTEM_IMAGE_PATH;
 
 jl_compileropts_t jl_compileropts = { NULL, // julia_home
+                                      NULL, // julia_bin
                                       NULL, // build_path
                                       system_image_path, // image_file
                                       0,    // code_coverage
@@ -436,7 +436,7 @@ static void jl_uv_exitcleanup_walk(uv_handle_t *handle, void *arg)
 void jl_write_coverage_data(void);
 void jl_write_malloc_log(void);
 
-DLLEXPORT void uv_atexit_hook()
+DLLEXPORT void jl_atexit_hook()
 {
 #if defined(JL_GC_MARKSWEEP) && defined(GC_FINAL_STATS)
     jl_print_gc_stats(JL_STDERR);
@@ -784,57 +784,53 @@ static void jl_resolve_sysimg_location()
 { // note: if you care about lost memory, you should compare the
   // pointers in jl_compileropts before and after calling julia_init()
   // and call the appropriate free function on the originals for any that changed
-    char *free_path = NULL;
+    char *free_path = (char*)malloc(PATH_MAX);
+    size_t path_size = PATH_MAX;
+    if (uv_exepath(free_path, &path_size)) {
+        ios_printf(ios_stderr, "fatal error: unexpected error while retrieving exepath\n");
+        exit(1);
+    }
+    if (path_size >= PATH_MAX) {
+        ios_printf(ios_stderr, "fatal error: jl_compileropts.julia_bin path too long\n");
+        exit(1);
+    }
+    jl_compileropts.julia_bin = strdup(free_path);
     if (!jl_compileropts.julia_home) {
         jl_compileropts.julia_home = getenv("JULIA_HOME");
         if (!jl_compileropts.julia_home) {
-            size_t path_size = PATH_MAX;
-            char *path = (char*)malloc(PATH_MAX);
-            if (uv_exepath(path, &path_size)) {
-                ios_printf(ios_stderr, "fatal error: unexpected error while retrieving exepath\n");
-                exit(1);
-            }
-            if (path_size >= PATH_MAX) {
-                ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
-                exit(1);
-            }
-            free_path = path;
-            jl_compileropts.julia_home = dirname(path);
+            jl_compileropts.julia_home = dirname(free_path);
         }
     }
     if (jl_compileropts.julia_home)
         jl_compileropts.julia_home = abspath(jl_compileropts.julia_home);
-    if (free_path) {
-        free(free_path);
-        free_path = NULL;
-    }
+    free(free_path);
+    free_path = NULL;
     if (jl_compileropts.image_file) {
         if (jl_compileropts.image_file[0] != PATHSEPSTRING[0]) {
             if (jl_compileropts.image_file == system_image_path) {
                 // build time path, relative to JULIA_HOME
-                char *path = (char*)malloc(PATH_MAX);
-                int n = snprintf(path, PATH_MAX, "%s" PATHSEPSTRING "%s",
+                free_path = (char*)malloc(PATH_MAX);
+                int n = snprintf(free_path, PATH_MAX, "%s" PATHSEPSTRING "%s",
                          jl_compileropts.julia_home, jl_compileropts.image_file);
                 if (n >= PATH_MAX || n < 0) {
                     ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
                     exit(1);
                 }
-                free_path = path;
-                jl_compileropts.image_file = path;
+                jl_compileropts.image_file = free_path;
             }
         }
-    }
-    if (jl_compileropts.image_file)
-        jl_compileropts.image_file = abspath(jl_compileropts.image_file);
-    if (free_path) {
-        free(free_path);
-        free_path = NULL;
+        if (jl_compileropts.image_file)
+            jl_compileropts.image_file = abspath(jl_compileropts.image_file);
+        if (free_path) {
+            free(free_path);
+            free_path = NULL;
+        }
     }
     if (jl_compileropts.build_path)
         jl_compileropts.build_path = abspath(jl_compileropts.build_path);
 }
 
-void julia_init()
+void _julia_init()
 {
     jl_io_loop = uv_default_loop(); // this loop will internal events (spawning process etc.),
                                     // best to call this first, since it also initializes libuv
@@ -926,11 +922,6 @@ void julia_init()
         jl_get_builtin_hooks();
         jl_boot_file_loaded = 1;
         jl_init_box_caches();
-        // Core.JULIA_HOME is a "magic" constant, we set it at runtime here
-        // since its value gets excluded from the system image
-        jl_set_const(jl_core_module, jl_symbol("JULIA_HOME"),
-                     jl_cstr_to_string(jl_compileropts.julia_home));
-        jl_module_export(jl_core_module, jl_symbol("JULIA_HOME"));
     }
 
     if (jl_compileropts.image_file) {
@@ -1105,18 +1096,8 @@ extern void *__stack_chk_guard;
 
 void jl_compile_all(void);
 
-DLLEXPORT int julia_trampoline(int argc, char **argv, int (*pmain)(int ac,char *av[]))
+DLLEXPORT int julia_save()
 {
-    unsigned char *p = (unsigned char *)&__stack_chk_guard;
-    char a = p[sizeof(__stack_chk_guard)-1];
-    char b = p[sizeof(__stack_chk_guard)-2];
-    char c = p[0];
-    /* If you have the ability to generate random numbers in your kernel then they should be used here */
-    p[sizeof(__stack_chk_guard)-1] = 255;
-    p[sizeof(__stack_chk_guard)-2] = '\n';
-    p[0] = 0;
-    JL_SET_STACK_BASE;
-    int ret = pmain(argc, argv);
     const char *build_path = jl_compileropts.build_path;
     if (build_path) {
         if (jl_compileropts.compile_enabled == JL_COMPILEROPT_COMPILE_ALL)
@@ -1148,10 +1129,6 @@ DLLEXPORT int julia_trampoline(int argc, char **argv, int (*pmain)(int ac,char *
             ios_printf(ios_stderr,"\nFATAL: failed to create string for .ji build path\n");
         }
     }
-    p[sizeof(__stack_chk_guard)-1] = a;
-    p[sizeof(__stack_chk_guard)-2] = b;
-    p[0] = c;
-    return ret;
 }
 
 jl_function_t *jl_typeinf_func=NULL;
diff --git a/src/jl_uv.c b/src/jl_uv.c
index 37615cbd156c8..6b68a895765e5 100644
--- a/src/jl_uv.c
+++ b/src/jl_uv.c
@@ -686,14 +686,10 @@ char *jl_bufptr(ios_t *s)
     return s->buf;
 }
 
-DLLEXPORT void uv_atexit_hook();
 DLLEXPORT void jl_exit(int exitcode)
 {
-    /*if (jl_io_loop) {
-        jl_process_events(&jl_io_loop);
-    }*/
     uv_tty_reset_mode();
-    uv_atexit_hook();
+    jl_atexit_hook();
     exit(exitcode);
 }
 
diff --git a/src/jlapi.c b/src/jlapi.c
index f3d94b2d2bc6b..1f24440ec353b 100644
--- a/src/jlapi.c
+++ b/src/jlapi.c
@@ -56,12 +56,6 @@ DLLEXPORT void jl_init(char *julia_home_dir)
 
 DLLEXPORT void *jl_eval_string(char *str)
 {
-#ifdef COPY_STACKS
-    int outside_task = (jl_root_task->stackbase == NULL);
-    if (outside_task) {
-        JL_SET_STACK_BASE;
-    }
-#endif
     jl_value_t *r;
     JL_TRY {
         jl_value_t *ast = jl_parse_input_line(str);
@@ -74,11 +68,6 @@ DLLEXPORT void *jl_eval_string(char *str)
         //jl_show(jl_stderr_obj(), jl_exception_in_transit);
         r = NULL;
     }
-#ifdef COPY_STACKS
-    if (outside_task) {
-        jl_root_task->stackbase = NULL;
-    }
-#endif
     return r;
 }
 
@@ -255,6 +244,21 @@ DLLEXPORT int jl_is_debugbuild(void)
 #endif
 }
 
+DLLEXPORT jl_value_t *jl_get_julia_home(void)
+{
+    return jl_cstr_to_string(jl_compileropts.julia_home);
+}
+
+DLLEXPORT jl_value_t *jl_get_julia_bin(void)
+{
+    return jl_cstr_to_string(jl_compileropts.julia_bin);
+}
+
+DLLEXPORT jl_value_t *jl_get_image_file(void)
+{
+    return jl_cstr_to_string(jl_compileropts.image_file);
+}
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/julia.h b/src/julia.h
index f0432ffba4f3e..d5d0be658786f 100644
--- a/src/julia.h
+++ b/src/julia.h
@@ -814,7 +814,6 @@ DLLEXPORT jl_value_t *jl_eqtable_get(jl_array_t *h, void *key, jl_value_t *deflt
 DLLEXPORT int jl_errno(void);
 DLLEXPORT void jl_set_errno(int e);
 DLLEXPORT int32_t jl_stat(const char *path, char *statbuf);
-DLLEXPORT void NORETURN jl_exit(int status);
 DLLEXPORT int jl_cpu_cores(void);
 DLLEXPORT long jl_getpagesize(void);
 DLLEXPORT long jl_getallocationgranularity(void);
@@ -856,11 +855,13 @@ DLLEXPORT void jl_exception_clear(void);
     }
 
 // initialization functions
-DLLEXPORT void julia_init();
+DLLEXPORT void julia_init(void);
 DLLEXPORT void jl_init(char *julia_home_dir);
 DLLEXPORT void jl_init_with_image(char *julia_home_dir, char *image_relative_path);
 DLLEXPORT int jl_is_initialized(void);
 DLLEXPORT int julia_trampoline(int argc, char *argv[], int (*pmain)(int ac,char *av[]));
+DLLEXPORT void jl_atexit_hook(void);
+DLLEXPORT void NORETURN jl_exit(int status);
 
 DLLEXPORT void jl_save_system_image(const char *fname);
 DLLEXPORT void jl_restore_system_image(const char *fname);
@@ -989,22 +990,6 @@ DLLEXPORT jl_value_t *jl_call3(jl_function_t *f, jl_value_t *a, jl_value_t *b, j
 
 // interfacing with Task runtime
 DLLEXPORT void jl_yield();
-DLLEXPORT void jl_handle_stack_start();
-
-#ifdef COPY_STACKS
-// initialize base context of root task
-extern DLLEXPORT jl_jmp_buf jl_base_ctx;
-#define JL_SET_STACK_BASE                               \
-    do {                                                \
-        int __stk;                                      \
-        jl_root_task->stackbase = (char*)&__stk;        \
-        if (jl_setjmp(jl_base_ctx, 1)) {                \
-            jl_handle_stack_start();                    \
-        }                                               \
-    } while (0)
-#else
-#define JL_SET_STACK_BASE
-#endif
 
 // gc -------------------------------------------------------------------------
 
@@ -1148,10 +1133,9 @@ typedef struct _jl_task_t {
     jl_value_t *exception;
     jl_function_t *start;
     jl_jmp_buf ctx;
-    union {
-        void *stackbase;
-        void *stack;
-    };
+#ifndef COPY_STACKS
+    void *stack;
+#endif
     size_t bufsz;
     void *stkbuf;
     size_t ssize;
@@ -1328,6 +1312,7 @@ void show_execution_point(char *filename, int lno);
 
 typedef struct {
     const char *julia_home;
+    const char *julia_bin;
     const char *build_path;
     const char *image_file;
     int8_t code_coverage;
@@ -1357,6 +1342,26 @@ extern DLLEXPORT jl_compileropts_t jl_compileropts;
 #define JL_COMPILEROPT_DUMPBITCODE_ON 1
 #define JL_COMPILEROPT_DUMPBITCODE_OFF 2
 
+extern void *__stack_chk_guard;
+#define SET_STACK_CHK_GUARD(a,b,c) do {                         \
+        unsigned char *p = (unsigned char *)&__stack_chk_guard; \
+        a = p[sizeof(__stack_chk_guard)-1];                     \
+        b = p[sizeof(__stack_chk_guard)-2];                     \
+        c = p[0];                                               \
+        /* If you have the ability to generate random numbers
+         * in your kernel then they should be used here */      \
+        p[sizeof(__stack_chk_guard)-1] = 255;                   \
+        p[sizeof(__stack_chk_guard)-2] = '\n';                  \
+        p[0] = 0;                                               \
+    } while (0)
+
+#define CLR_STACK_CHK_GUARD(a,b,c) do {                         \
+        unsigned char *p = (unsigned char *)&__stack_chk_guard; \
+        p[sizeof(__stack_chk_guard)-1] = a;                     \
+        p[sizeof(__stack_chk_guard)-2] = b;                     \
+        p[0] = c;                                               \
+    } while (0)
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/julia_internal.h b/src/julia_internal.h
index 9df408979c9be..5b45ec65403cc 100644
--- a/src/julia_internal.h
+++ b/src/julia_internal.h
@@ -81,12 +81,16 @@ extern size_t jl_arr_xtralloc_limit;
 
 void jl_init_types(void);
 void jl_init_box_caches(void);
-DLLEXPORT void jl_init_frontend(void);
+void jl_init_frontend(void);
 void jl_init_primitives(void);
 void jl_init_codegen(void);
 void jl_init_intrinsic_functions(void);
 void jl_init_tasks(void *stack, size_t ssize);
 void jl_init_serializer(void);
+void _julia_init(void);
+#ifdef COPY_STACKS
+extern void *jl_stackbase;
+#endif
 
 void jl_dump_bitcode(char *fname);
 void jl_dump_objfile(char *fname, int jit_model);
@@ -141,6 +145,8 @@ extern uv_lib_t *jl_crtdll_handle;
 extern uv_lib_t *jl_winsock_handle;
 #endif
 
+DLLEXPORT void jl_atexit_hook();
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/task.c b/src/task.c
index 4fc7a0764d088..e2945a32c5f4a 100644
--- a/src/task.c
+++ b/src/task.c
@@ -154,18 +154,24 @@ jl_value_t *jl_exception_in_transit;
 jl_gcframe_t *jl_pgcstack = NULL;
 #endif
 
-static void start_task(jl_task_t *t);
-
 #ifdef COPY_STACKS
-jl_jmp_buf * volatile jl_jmp_target;
-DLLEXPORT jl_jmp_buf jl_base_ctx;
+static jl_jmp_buf * volatile jl_jmp_target;
+
+#if defined(_CPU_X86_64_) || defined(_CPU_X86_)
+#define ASM_COPY_STACKS
+#endif
+void *jl_stackbase;
+
+#ifndef ASM_COPY_STACKS
+static jl_jmp_buf jl_base_ctx; // base context of stack
+#endif
 
 static void save_stack(jl_task_t *t)
 {
     if (t->state == done_sym || t->state == failed_sym)
         return;
     volatile int _x;
-    size_t nb = (char*)t->stackbase - (char*)&_x;
+    size_t nb = (char*)jl_stackbase - (char*)&_x;
     char *buf;
     if (t->stkbuf == NULL || t->bufsz < nb) {
         buf = (char*)allocb(nb);
@@ -180,12 +186,13 @@ static void save_stack(jl_task_t *t)
 }
 
 #if defined(_OS_WINDOWS_) && !defined(_COMPILER_MINGW_)
-void __declspec(noinline) restore_stack(jl_task_t *t, jl_jmp_buf *where, char *p)
+void __declspec(noinline)
 #else
-void __attribute__((noinline)) restore_stack(jl_task_t *t, jl_jmp_buf *where, char *p)
+void __attribute__((noinline))
 #endif
+restore_stack(jl_task_t *t, jl_jmp_buf *where, char *p)
 {
-    char *_x = (char*)t->stackbase - t->ssize;
+    char *_x = (char*)jl_stackbase - t->ssize;
     if (!p) {
         p = _x;
         if ((char*)&_x > _x) {
@@ -202,6 +209,94 @@ void __attribute__((noinline)) restore_stack(jl_task_t *t, jl_jmp_buf *where, ch
 }
 #endif
 
+static jl_function_t *task_done_hook_func=NULL;
+
+static void NORETURN finish_task(jl_task_t *t, jl_value_t *resultval)
+{
+    if (t->exception != jl_nothing)
+        t->state = failed_sym;
+    else
+        t->state = done_sym;
+    t->result = resultval;
+    // TODO: early free of t->stkbuf
+#ifdef COPY_STACKS
+    t->stkbuf = NULL;
+#endif
+    if (task_done_hook_func == NULL) {
+        task_done_hook_func = (jl_function_t*)jl_get_global(jl_base_module,
+                                                            jl_symbol("task_done_hook"));
+    }
+    if (task_done_hook_func != NULL) {
+        jl_apply(task_done_hook_func, (jl_value_t**)&t, 1);
+    }
+    abort();
+}
+
+#if defined(_OS_WINDOWS_) && !defined(_COMPILER_MINGW_)
+void __declspec(noinline)
+#else
+void __attribute__((noinline))
+#endif
+NORETURN start_task()
+{
+    // this runs the first time we switch to a task
+    jl_task_t *t = jl_current_task;
+    jl_value_t *arg = jl_task_arg_in_transit;
+    jl_value_t *res;
+    JL_GC_PUSH1(&arg);
+    res = jl_apply(t->start, NULL, 0);
+    JL_GC_POP();
+    finish_task(t, res);
+    abort();
+}
+
+#ifndef ASM_COPY_STACKS
+#if defined(_OS_WINDOWS_) && !defined(_COMPILER_MINGW_)
+static void __declspec(noinline)
+#else
+static void __attribute__((noinline))
+#endif
+set_base_ctx(char *__stk)
+{
+    if (jl_setjmp(jl_base_ctx, 1)) {
+        start_task();
+    }
+}
+#else
+void set_base_ctx(char *__stk) { }
+#endif
+
+
+DLLEXPORT void julia_init()
+{ // keep this function small, since we want to keep the stack frame
+  // leading up to this also quite small
+    _julia_init();
+#ifdef COPY_STACKS
+    char __stk;
+    jl_stackbase = (char*)(((uptrint_t)&__stk + sizeof(__stk))&-16); // also ensures stackbase is 16-byte aligned
+    set_base_ctx(&__stk); // separate function, to record the size of a stack frame
+#endif
+}
+
+#ifndef COPY_STACKS
+static void init_task(jl_task_t *t)
+{
+    if (jl_setjmp(t->ctx, 0)) {
+        start_task();
+    }
+    // this runs when the task is created
+    ptrint_t local_sp = (ptrint_t)&t;
+    ptrint_t new_sp = (ptrint_t)t->stack + t->ssize - _frame_offset;
+#ifdef _P64
+    // SP must be 16-byte aligned
+    new_sp = new_sp&-16;
+    local_sp = local_sp&-16;
+#endif
+    memcpy((void*)new_sp, (void*)local_sp, _frame_offset);
+    rebase_state(&t->ctx, local_sp, new_sp);
+}
+#endif
+
 static void ctx_switch(jl_task_t *t, jl_jmp_buf *where)
 {
     if (t == jl_current_task)
@@ -248,7 +343,25 @@ static void ctx_switch(jl_task_t *t, jl_jmp_buf *where)
         if (t->stkbuf) {
             restore_stack(t, where, NULL);
         } else {
+#ifdef ASM_COPY_STACKS
+#ifdef _CPU_X86_64_
+            asm(" movq %0, %%rsp;\n"
+                " xorq %%rbp, %%rbp;\n"
+                " push %%rbp;\n" // instead of RSP
+                " jmp _start_task" // call stack_task with fake stack frame
+                : : "r"(jl_stackbase-0x10) : );
+#elif defined(_CPU_X86_)
+            asm(" movl %0, %%esp;\n"
+                " xorl %%ebp, %%ebp;\n"
+                " push %%ebp;\n" // instead of ESP
+                " jmp _start_task" // call stack_task with fake stack frame
+                : : "r"(jl_stackbase-0x10) : );
+#else
+#error ASM_COPY_STACKS not supported on this platform
+#endif
+#else // ASM_COPY_STACKS
             jl_longjmp(jl_base_ctx, 1);
+#endif
         }
 #else
         jl_longjmp(*where, 1);
@@ -368,74 +481,6 @@ jl_value_t *jl_switchto(jl_task_t *t, jl_value_t *arg)
     return switchto(t);
 }
 
-static jl_function_t *task_done_hook_func=NULL;
-
-static void finish_task(jl_task_t *t, jl_value_t *resultval)
-{
-    if (t->exception != jl_nothing)
-        t->state = failed_sym;
-    else
-        t->state = done_sym;
-    t->result = resultval;
-    // TODO: early free of t->stkbuf
-#ifdef COPY_STACKS
-    t->stkbuf = NULL;
-#endif
-    if (task_done_hook_func == NULL) {
-        task_done_hook_func = (jl_function_t*)jl_get_global(jl_base_module,
-                                                            jl_symbol("task_done_hook"));
-    }
-    if (task_done_hook_func != NULL) {
-        jl_apply(task_done_hook_func, (jl_value_t**)&t, 1);
-    }
-    assert(0);
-}
-
-static void start_task(jl_task_t *t)
-{
-    // this runs the first time we switch to t
-    jl_value_t *arg = jl_task_arg_in_transit;
-    jl_value_t *res;
-    JL_GC_PUSH1(&arg);
-
-#ifdef COPY_STACKS
-    ptrint_t local_sp = (ptrint_t)jl_pgcstack;
-    // here we attempt to figure out how big our stack frame is, since we
-    // might need to copy all of it later. this is a bit of a fuzzy guess.
-    local_sp += sizeof(jl_gcframe_t);
-    local_sp += 12*sizeof(void*);
-    t->stackbase = (void*)(local_sp + _frame_offset);
-#endif
-    res = jl_apply(t->start, NULL, 0);
-    JL_GC_POP();
-    finish_task(t, res);
-    assert(0);
-}
-
-DLLEXPORT void jl_handle_stack_start()
-{
-    start_task(jl_current_task);
-}
-
-#ifndef COPY_STACKS
-static void init_task(jl_task_t *t)
-{
-    if (jl_setjmp(t->ctx, 0)) {
-        start_task(t);
-    }
-    // this runs when the task is created
-    ptrint_t local_sp = (ptrint_t)&t;
-    ptrint_t new_sp = (ptrint_t)t->stack + t->ssize - _frame_offset;
-#ifdef _P64
-    // SP must be 16-byte aligned
-    new_sp = new_sp&-16;
-    local_sp = local_sp&-16;
-#endif
-    memcpy((void*)new_sp, (void*)local_sp, _frame_offset);
-    rebase_state(&t->ctx, local_sp, new_sp);
-}
-#endif
-
 ptrint_t bt_data[MAX_BT_SIZE+1];
 size_t bt_size = 0;
 
@@ -581,9 +626,8 @@ DLLEXPORT size_t rec_backtrace_ctx(ptrint_t *data, size_t maxsize, unw_context_t
     do {
         if (n >= maxsize)
             break;
-        if (unw_get_reg(&cursor, UNW_REG_IP, &ip) < 0) {
+        if (unw_get_reg(&cursor, UNW_REG_IP, &ip) < 0)
             break;
-        }
         data[n++] = ip;
     } while (unw_step(&cursor) > 0);
     return n;
@@ -602,9 +646,8 @@ size_t rec_backtrace_ctx_dwarf(ptrint_t *data, size_t maxsize, unw_context_t *uc
     do {
         if (n >= maxsize)
             break;
-        if (unw_get_reg(&cursor, UNW_REG_IP, &ip) < 0) {
+        if (unw_get_reg(&cursor, UNW_REG_IP, &ip) < 0)
             break;
-        }
         data[n++] = ip;
     } while (unw_step(&cursor) > 0);
     return n;
@@ -849,7 +892,6 @@ void jl_init_tasks(void *stack, size_t ssize)
     jl_current_task = (jl_task_t*)allocobj(sizeof(jl_task_t));
     jl_current_task->type = (jl_value_t*)jl_task_type;
 #ifdef COPY_STACKS
-    jl_current_task->stackbase = NULL;
     jl_current_task->ssize = 0;  // size of saved piece
     jl_current_task->bufsz = 0;
 #else
diff --git a/ui/repl.c b/ui/repl.c
index 49e68a4bbc162..88aa0c479ec09 100644
--- a/ui/repl.c
+++ b/ui/repl.c
@@ -256,7 +256,7 @@ static void print_profile(void)
 }
 #endif
 
-int true_main(int argc, char *argv[])
+static int true_main(int argc, char *argv[])
 {
     if (jl_base_module != NULL) {
         jl_array_t *args = (jl_array_t*)jl_get_global(jl_base_module, jl_symbol("ARGS"));
@@ -308,10 +308,11 @@ int true_main(int argc, char *argv[])
         JL_PUTS("\n",JL_STDOUT);
         goto again;
     }
-    uv_tty_reset_mode();
     return iserr;
 }
 
+DLLEXPORT extern int julia_save();
+
 #ifndef _OS_WINDOWS_
 int main(int argc, char *argv[])
 {
@@ -329,6 +330,8 @@ int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
         argv[i] = (wchar_t*)arg;
     }
 #endif
+    char a,b,c;
+    SET_STACK_CHK_GUARD(a,b,c);
     libsupport_init();
     parse_opts(&argc, (char***)&argv);
     if (lisp_prompt) {
@@ -336,7 +339,11 @@ int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
         return 0;
     }
     julia_init();
-    return julia_trampoline(argc, (char**)argv, true_main);
+    int ret = true_main(argc, (char**)argv);
+    jl_atexit_hook();
+    julia_save();
+    CLR_STACK_CHK_GUARD(a,b,c);
+    return ret;
 }
 
 #ifdef __cplusplus

From c37f371c1ea26b0e2a7614a8536d94330546ee18 Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Fri, 12 Dec 2014 22:54:00 -0500
Subject: [PATCH 3/7] code cleanup

---
 base/client.jl        |  7 ++-----
 src/codegen.cpp       |  2 +-
 src/disasm.cpp        |  2 +-
 src/dump.c            |  6 ++----
 src/init.c            |  6 +++---
 src/julia.expmap      |  1 +
 src/julia.h           |  2 +-
 src/support/dirpath.h |  2 ++
 src/task.c            | 16 +++++++++-------
 ui/repl.c             |  2 +-
 10 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/base/client.jl b/base/client.jl
index db9de86654d25..27ca40edba1e1 100644
--- a/base/client.jl
+++ b/base/client.jl
@@ -426,11 +426,8 @@ function _start()
         println()
         exit(1)
     end
-    if is_interactive
-        if have_color
-            print(color_normal)
-        end
-        println()
+    if is_interactive && have_color
+        print(color_normal)
     end
 end
 
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 14c6194435d94..fce9e1c848f44 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -121,7 +121,7 @@ extern "C" {
 
 #include "builtin_proto.h"
 
-void *__stack_chk_guard = NULL;
+DLLEXPORT void *__stack_chk_guard = NULL;
 
 #if defined(_OS_WINDOWS_) && !defined(_COMPILER_MINGW_)
 void __stack_chk_fail()
diff --git a/src/disasm.cpp b/src/disasm.cpp
index 528d33b88be68..fdd998f84b252 100644
--- a/src/disasm.cpp
+++ b/src/disasm.cpp
@@ -482,7 +482,7 @@ void jl_dump_function_asm(const char *Fptr, size_t Fsize,
 #ifdef LLVM35
                         if (MCIA->evaluateBranch(Inst, Index, insSize, addr))
 #else
-                        if ((addr = MCIA->evaluateBranch(Inst, Index, insSize)) != -1)
+                        if ((addr = MCIA->evaluateBranch(Inst, Index, insSize)) != (uint64_t)-1)
 #endif
                             DisInfo.insertAddress(addr);
                     }
diff --git a/src/dump.c b/src/dump.c
index ac511abf1e3d7..3e4cb37701d0a 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -1330,10 +1330,8 @@ DLLEXPORT void jl_save_system_image(const char *fname)
     // save module initialization order
     if (jl_module_init_order != NULL) {
         for(i=0; i < jl_array_len(jl_module_init_order); i++) {
-            // NULL out any modules that weren't saved
-            jl_value_t *mod = jl_cellref(jl_module_init_order, i);
-            (void)mod;
-            assert(ptrhash_get(&backref_table, mod) != HT_NOTFOUND);
+            // verify that all these modules were saved
+            assert(ptrhash_get(&backref_table, jl_cellref(jl_module_init_order, i)) != HT_NOTFOUND);
         }
     }
     jl_serialize_value(&f, jl_module_init_order);
diff --git a/src/init.c b/src/init.c
index 0010bf484e882..ec1181508645e 100644
--- a/src/init.c
+++ b/src/init.c
@@ -765,13 +765,13 @@ static char *abspath(const char *in)
         }
     }
 #else
-    DWORD n = GetFullPathName(in, 0, NULL, C_NULL);
+    DWORD n = GetFullPathName(in, 0, NULL, NULL);
     if (n <= 0) {
         ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long or GetFullPathName failed\n");
         exit(1);
     }
     char *out = (char*)malloc(n);
-    DWORD m = GetFullPathName(in, n, out, C_NULL);
+    DWORD m = GetFullPathName(in, n, out, NULL);
     if (n != m + 1) {
         ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long or GetFullPathName failed\n");
         exit(1);
@@ -1096,7 +1096,7 @@ extern void *__stack_chk_guard;
 
 void jl_compile_all(void);
 
-DLLEXPORT int julia_save()
+DLLEXPORT void julia_save()
 {
     const char *build_path = jl_compileropts.build_path;
     if (build_path) {
diff --git a/src/julia.expmap b/src/julia.expmap
index 08f54c22f5a0c..40edbbba6a1dc 100644
--- a/src/julia.expmap
+++ b/src/julia.expmap
@@ -1,6 +1,7 @@
 {
   global:
     __asan*;
+    __stack_chk_guard;
     alloc_*w;
     allocobj;
     asprintf;
diff --git a/src/julia.h b/src/julia.h
index d5d0be658786f..ada5811a7d900 100644
--- a/src/julia.h
+++ b/src/julia.h
@@ -1342,7 +1342,7 @@ extern DLLEXPORT jl_compileropts_t jl_compileropts;
 #define JL_COMPILEROPT_DUMPBITCODE_ON 1
 #define JL_COMPILEROPT_DUMPBITCODE_OFF 2
 
-extern void *__stack_chk_guard;
+DLLEXPORT extern void *__stack_chk_guard;
 #define SET_STACK_CHK_GUARD(a,b,c) do {                         \
         unsigned char *p = (unsigned char *)&__stack_chk_guard; \
         a = p[sizeof(__stack_chk_guard)-1];                     \
diff --git a/src/support/dirpath.h b/src/support/dirpath.h
index 28fff4ab96def..e906ddd7521b2 100644
--- a/src/support/dirpath.h
+++ b/src/support/dirpath.h
@@ -10,7 +10,9 @@
 #else
 #define PATHSEPSTRING "/"
 #define PATHLISTSEPSTRING ":"
+#ifndef PATH_MAX // many platforms don't have a max path, we define one anyways
 #define PATH_MAX 1024
 #endif
+#endif
 
 #endif
diff --git a/src/task.c b/src/task.c
index e2945a32c5f4a..cc6f8024f4f79 100644
--- a/src/task.c
+++ b/src/task.c
@@ -233,9 +233,9 @@ static void NORETURN finish_task(jl_task_t *t, jl_value_t *resultval)
 }
 
 #if defined(_OS_WINDOWS_) && !defined(_COMPILER_MINGW_)
-void __declspec(noinline)
+static void __declspec(noinline)
 #else
-void __attribute__((noinline))
+static void __attribute__((noinline))
 #endif
 NORETURN start_task()
 {
@@ -348,16 +348,18 @@ static void ctx_switch(jl_task_t *t, jl_jmp_buf *where)
             asm(" movq %0, %%rsp;\n"
                 " xorq %%rbp, %%rbp;\n"
                 " push %%rbp;\n" // instead of RSP
-                " jmp _start_task" // call stack_task with fake stack frame
-                : : "r"(jl_stackbase-0x10) : );
+                " jmp %P1;\n" // call stack_task with fake stack frame
+                " ud2"
+                : : "r"(jl_stackbase-0x10), "i"(start_task) : "memory" );
 #elif defined(_CPU_X86_)
             asm(" movl %0, %%esp;\n"
                 " xorl %%ebp, %%ebp;\n"
                 " push %%ebp;\n" // instead of ESP
-                " jmp _start_task" // call stack_task with fake stack frame
-                : : "r"(jl_stackbase-0x10) : );
+                " jmp %P1;\n" // call stack_task with fake stack frame
+                " ud2"
+                : : "r"(jl_stackbase-0x10), "i"(start_task) : "memory" );
 #else
-#error ASM_COPY_STACKS not supported on this platform
+#error ASM_COPY_STACKS not supported on this cpu architecture
 #endif
 #else // ASM_COPY_STACKS
             jl_longjmp(jl_base_ctx, 1);
diff --git a/ui/repl.c b/ui/repl.c
index 88aa0c479ec09..e758b250ba823 100644
--- a/ui/repl.c
+++ b/ui/repl.c
@@ -311,7 +311,7 @@ static int true_main(int argc, char *argv[])
     return iserr;
 }
 
-DLLEXPORT extern int julia_save();
+DLLEXPORT extern void julia_save();
 
 #ifndef _OS_WINDOWS_
 int main(int argc, char *argv[])

From 8203538c7f621000cf8fc8fa1509c50c2b83a8dd Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sat, 13 Dec 2014 23:12:19 -0500
Subject: [PATCH 4/7] remove extraneous gc root in start_task

---
 src/task.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/task.c b/src/task.c
index cc6f8024f4f79..6c10904839264 100644
--- a/src/task.c
+++ b/src/task.c
@@ -241,11 +241,8 @@ NORETURN start_task()
 {
     // this runs the first time we switch to a task
     jl_task_t *t = jl_current_task;
-    jl_value_t *arg = jl_task_arg_in_transit;
     jl_value_t *res;
-    JL_GC_PUSH1(&arg);
     res = jl_apply(t->start, NULL, 0);
-    JL_GC_POP();
     finish_task(t, res);
     abort();
 }

From e2cb463f89ed52aabfc7cb487b5daf2d13dd3e4b Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sat, 13 Dec 2014 23:50:30 -0500
Subject: [PATCH 5/7] allow the user to specify whether the image_file should
 be interpreted relative to JULIA_HOME or CWD

---
 src/init.c           | 42 +++++++++++++++++++++++++++++-------------
 src/jlapi.c          |  2 +-
 src/julia.h          |  7 ++++++-
 src/julia_internal.h |  2 +-
 src/task.c           |  4 ++--
 ui/repl.c            |  4 ++--
 6 files changed, 41 insertions(+), 20 deletions(-)

diff --git a/src/init.c b/src/init.c
index ec1181508645e..cd2288df6d196 100644
--- a/src/init.c
+++ b/src/init.c
@@ -780,7 +780,7 @@ static char *abspath(const char *in)
     return out;
 }
 
-static void jl_resolve_sysimg_location()
+static void jl_resolve_sysimg_location(JL_IMAGE_SEARCH rel)
 { // note: if you care about lost memory, you should compare the
   // pointers in jl_compileropts before and after calling julia_init()
   // and call the appropriate free function on the originals for any that changed
@@ -806,18 +806,34 @@ static void jl_resolve_sysimg_location()
     free(free_path);
     free_path = NULL;
     if (jl_compileropts.image_file) {
-        if (jl_compileropts.image_file[0] != PATHSEPSTRING[0]) {
-            if (jl_compileropts.image_file == system_image_path) {
-                // build time path, relative to JULIA_HOME
-                free_path = (char*)malloc(PATH_MAX);
-                int n = snprintf(free_path, PATH_MAX, "%s" PATHSEPSTRING "%s",
-                         jl_compileropts.julia_home, jl_compileropts.image_file);
-                if (n >= PATH_MAX || n < 0) {
-                    ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
-                    exit(1);
+        if (rel == JL_IMAGE_JULIA_HOME) {
+#ifdef _OS_WINDOWS_
+            char c0 = jl_compileropts.image_file[0];
+            if (c0 == '/' || c0 == '\\') {
+                rel = 0; // absolute path relative to %CD% (current drive)
+            }
+            else {
+                int s = strlen(jl_compileropts.image_file);
+                if (s > 2) {
+                    char c1 = jl_compileropts.image_file[1];
+                    char c2 = jl_compileropts.image_file[2];
+                    if (c1 == ':' && (c2 == '/' || c2 == '\\')) rel = 0; // absolute path
                 }
-                jl_compileropts.image_file = free_path;
             }
+#else
+            if (jl_compileropts.image_file[0] == '/') rel = 0; // absolute path
+#endif
+        }
+        if (rel == JL_IMAGE_JULIA_HOME) {
+            // build time path, relative to JULIA_HOME
+            free_path = (char*)malloc(PATH_MAX);
+            int n = snprintf(free_path, PATH_MAX, "%s" PATHSEPSTRING "%s",
+                     jl_compileropts.julia_home, jl_compileropts.image_file);
+            if (n >= PATH_MAX || n < 0) {
+                ios_printf(ios_stderr, "fatal error: jl_compileropts.image_file path too long\n");
+                exit(1);
+            }
+            jl_compileropts.image_file = free_path;
         }
         if (jl_compileropts.image_file)
             jl_compileropts.image_file = abspath(jl_compileropts.image_file);
@@ -830,11 +846,11 @@ static void jl_resolve_sysimg_location()
         jl_compileropts.build_path = abspath(jl_compileropts.build_path);
 }
 
-void _julia_init()
+void _julia_init(JL_IMAGE_SEARCH rel)
 {
     jl_io_loop = uv_default_loop(); // this loop will internal events (spawning process etc.),
                                     // best to call this first, since it also initializes libuv
-    jl_resolve_sysimg_location();
+    jl_resolve_sysimg_location(rel);
     jl_page_size = jl_getpagesize();
     jl_arr_xtralloc_limit = uv_get_total_memory() / 100;  // Extra allocation limited to 1% of total RAM
     jl_find_stack_bottom();
diff --git a/src/jlapi.c b/src/jlapi.c
index 1f24440ec353b..006482e50d921 100644
--- a/src/jlapi.c
+++ b/src/jlapi.c
@@ -39,7 +39,7 @@ DLLEXPORT void jl_init_with_image(char *julia_home_dir, char *image_relative_pat
     jl_compileropts.julia_home = julia_home_dir;
     if (image_relative_path != NULL)
         jl_compileropts.image_file = image_relative_path;
-    julia_init();
+    julia_init(JL_IMAGE_JULIA_HOME);
     //TODO: these should be part of Multi.__init__()
     //currently, we have them here since we may not want them
     //getting unconditionally set from Base.__init__()
diff --git a/src/julia.h b/src/julia.h
index ada5811a7d900..f3ad38c84f7a3 100644
--- a/src/julia.h
+++ b/src/julia.h
@@ -855,7 +855,12 @@ DLLEXPORT void jl_exception_clear(void);
     }
 
 // initialization functions
-DLLEXPORT void julia_init(void);
+typedef enum {
+    JL_IMAGE_CWD = 0,
+    JL_IMAGE_JULIA_HOME = 1,
+    //JL_IMAGE_LIBJULIA = 2,
+} JL_IMAGE_SEARCH;
+DLLEXPORT void julia_init(JL_IMAGE_SEARCH rel);
 DLLEXPORT void jl_init(char *julia_home_dir);
 DLLEXPORT void jl_init_with_image(char *julia_home_dir, char *image_relative_path);
 DLLEXPORT int jl_is_initialized(void);
diff --git a/src/julia_internal.h b/src/julia_internal.h
index 5b45ec65403cc..25a44e873680a 100644
--- a/src/julia_internal.h
+++ b/src/julia_internal.h
@@ -87,7 +87,7 @@ void jl_init_codegen(void);
 void jl_init_intrinsic_functions(void);
 void jl_init_tasks(void *stack, size_t ssize);
 void jl_init_serializer(void);
-void _julia_init(void);
+void _julia_init(JL_IMAGE_SEARCH rel);
 #ifdef COPY_STACKS
 extern void *jl_stackbase;
 #endif
diff --git a/src/task.c b/src/task.c
index 6c10904839264..01d551509d564 100644
--- a/src/task.c
+++ b/src/task.c
@@ -264,10 +264,10 @@ void set_base_ctx(char *__stk) { }
 #endif
 
 
-DLLEXPORT void julia_init()
+DLLEXPORT void julia_init(JL_IMAGE_SEARCH rel)
 { // keep this function small, since we want to keep the stack frame
   // leading up to this also quite small
-    _julia_init();
+    _julia_init(rel);
 #ifdef COPY_STACKS
     char __stk;
     jl_stackbase = (char*)(((uptrint_t)&__stk + sizeof(__stk))&-16); // also ensures stackbase is 16-byte aligned
diff --git a/ui/repl.c b/ui/repl.c
index e758b250ba823..0c18ec88b1144 100644
--- a/ui/repl.c
+++ b/ui/repl.c
@@ -40,6 +40,7 @@ static int lisp_prompt = 0;
 static int codecov  = JL_LOG_NONE;
 static int malloclog= JL_LOG_NONE;
 static char *program = NULL;
+static int imagepathspecified = 0;
 
 static const char *usage = "julia [options] [program] [args...]\n";
 static const char *opts =
@@ -95,7 +96,6 @@ void parse_opts(int *argcp, char ***argvp)
     };
     int c;
     opterr = 0;
-    int imagepathspecified=0;
     int skip = 0;
     int lastind = optind;
     while ((c = getopt_long(*argcp,*argvp,shortopts,longopts,0)) != -1) {
@@ -338,7 +338,7 @@ int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
         jl_lisp_prompt();
         return 0;
     }
-    julia_init();
+    julia_init(imagepathspecified ? JL_IMAGE_CWD : JL_IMAGE_JULIA_HOME);
     int ret = true_main(argc, (char**)argv);
     jl_atexit_hook();
     julia_save();

From 9da3b57d9f10affa6039d58860e426f2b96be33d Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sun, 14 Dec 2014 00:09:40 -0500
Subject: [PATCH 6/7] update embedding doc to be consistent with changes to
 julia_init

---
 doc/manual/embedding.rst | 18 ++++++++++++++++--
 examples/embedding.c     |  5 ++++-
 src/init.c               |  1 +
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/doc/manual/embedding.rst b/doc/manual/embedding.rst
index a5a0cdb1a73c3..230d3c5b953ad 100644
--- a/doc/manual/embedding.rst
+++ b/doc/manual/embedding.rst
@@ -18,11 +18,25 @@ We start with a simple C program that initializes Julia and calls some Julia cod
 
   int main(int argc, char *argv[])
   {
+      /* optional: randomize the stack guard */
+      char a, b, c;
+      SET_STACK_CHK_GUARD(a,b,c);
+
+      /* required: setup the julia context */
       jl_init(NULL);
-      JL_SET_STACK_BASE;
 
+      /* run julia commands */
       jl_eval_string("print(sqrt(2.0))");
 
+      /* strongly recommended: notify julia that the
+           program is about to terminate. this allows
+           julia time to cleanup pending write requests
+           and run all finalizers
+      */
+      jl_atexit_hook();
+
+      /* if the stack guard is set: reset the stack guard */
+      CLR_STACK_CHK_GUARD(a,b,c);
       return 0;
   }
 
@@ -30,7 +44,7 @@ In order to build this program you have to put the path to the Julia header into
 
     gcc -o test -I$JULIA_DIR/include/julia -L$JULIA_DIR/usr/lib -ljulia test.c
 
-Alternatively, look at the ``embedding.c`` program in the julia source tree in the ``examples/`` folder.
+Alternatively, look at the ``embedding.c`` program in the julia source tree in the ``examples/`` folder. The file ``ui/repl.c`` program is another simple example of how to set ``jl_compileropts`` options while linking against libjulia.
 
 The first thing that has to be done before calling any other Julia C function is to initialize Julia. This is done by calling ``jl_init``, which takes as argument a C string (``const char*``) to the location where Julia is installed. When the argument is ``NULL``, Julia tries to determine the install location automatically.
 
diff --git a/examples/embedding.c b/examples/embedding.c
index f9ab53ae9e9e9..fadfd70c997de 100644
--- a/examples/embedding.c
+++ b/examples/embedding.c
@@ -9,8 +9,9 @@ double my_c_sqrt(double x)
 
 int main()
 {
+    char a, b, c;
+    SET_STACK_CHK_GUARD(a,b,c);
     jl_init(NULL);
-    JL_SET_STACK_BASE;
 
     {
         // Simple running Julia code
@@ -94,5 +95,7 @@ int main()
         }
     }
 
+    jl_atexit_hook();
+    CLR_STACK_CHK_GUARD(a,b,c);
     return 0;
 }
diff --git a/src/init.c b/src/init.c
index cd2288df6d196..335d82d152d5b 100644
--- a/src/init.c
+++ b/src/init.c
@@ -848,6 +848,7 @@ static void jl_resolve_sysimg_location(JL_IMAGE_SEARCH rel)
 
 void _julia_init(JL_IMAGE_SEARCH rel)
 {
+    libsupport_init();
     jl_io_loop = uv_default_loop(); // this loop will internal events (spawning process etc.),
                                     // best to call this first, since it also initializes libuv
     jl_resolve_sysimg_location(rel);

From dc8c12addcae4a162b319119295820a14842fb5b Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Sun, 14 Dec 2014 00:42:05 -0500
Subject: [PATCH 7/7] some more init cleanup, and comments

---
 src/init.c  | 51 +++++++++++++++++++++++++++++----------------------
 ui/Makefile |  1 -
 2 files changed, 29 insertions(+), 23 deletions(-)

diff --git a/src/init.c b/src/init.c
index 335d82d152d5b..8ec4fb1138549 100644
--- a/src/init.c
+++ b/src/init.c
@@ -739,6 +739,27 @@ kern_return_t catch_exception_raise(mach_port_t            exception_port,
 
 #endif
 
+static int isabspath(const char *in)
+{
+#ifdef _OS_WINDOWS_
+    char c0 = in[0];
+    if (c0 == '/' || c0 == '\\') {
+        return 1; // absolute path relative to %CD% (current drive), or UNC
+    }
+    else {
+        int s = strlen(in);
+        if (s > 2) {
+            char c1 = in[1];
+            char c2 = in[2];
+            if (c1 == ':' && (c2 == '/' || c2 == '\\')) return 1; // absolute path
+        }
+    }
+#else
+    if (jl_compileropts.image_file[0] == '/') return 1; // absolute path
+#endif
+    return 0; // relative path
+}
+
 static char *abspath(const char *in)
 { // compute an absolute path location, so that chdir doesn't change the file reference
 #ifndef _OS_WINDOWS_
@@ -781,9 +802,13 @@ static char *abspath(const char *in)
 }
 
 static void jl_resolve_sysimg_location(JL_IMAGE_SEARCH rel)
-{ // note: if you care about lost memory, you should compare the
-  // pointers in jl_compileropts before and after calling julia_init()
-  // and call the appropriate free function on the originals for any that changed
+{ // this function resolves the paths in jl_compileropts to absolute file locations as needed
+  // and it replaces the pointers to `julia_home`, `julia_bin`, `image_file`, and `build_path`
+  // it may fail, print an error, and exit(1) if any of these paths are longer than PATH_MAX
+  //
+  // note: if you care about lost memory, you should call the appropriate `free()` function
+  // on the original pointer for each `char*` you've inserted into `jl_compileropts`, after
+  // calling `julia_init()`
     char *free_path = (char*)malloc(PATH_MAX);
     size_t path_size = PATH_MAX;
     if (uv_exepath(free_path, &path_size)) {
@@ -806,25 +831,7 @@ static void jl_resolve_sysimg_location(JL_IMAGE_SEARCH rel)
     free(free_path);
     free_path = NULL;
     if (jl_compileropts.image_file) {
-        if (rel == JL_IMAGE_JULIA_HOME) {
-#ifdef _OS_WINDOWS_
-            char c0 = jl_compileropts.image_file[0];
-            if (c0 == '/' || c0 == '\\') {
-                rel = 0; // absolute path relative to %CD% (current drive)
-            }
-            else {
-                int s = strlen(jl_compileropts.image_file);
-                if (s > 2) {
-                    char c1 = jl_compileropts.image_file[1];
-                    char c2 = jl_compileropts.image_file[2];
-                    if (c1 == ':' && (c2 == '/' || c2 == '\\')) rel = 0; // absolute path
-                }
-            }
-#else
-            if (jl_compileropts.image_file[0] == '/') rel = 0; // absolute path
-#endif
-        }
-        if (rel == JL_IMAGE_JULIA_HOME) {
+        if (rel == JL_IMAGE_JULIA_HOME && !isabspath(jl_compileropts.image_file)) {
             // build time path, relative to JULIA_HOME
             free_path = (char*)malloc(PATH_MAX);
             int n = snprintf(free_path, PATH_MAX, "%s" PATHSEPSTRING "%s",
diff --git a/ui/Makefile b/ui/Makefile
index 181e79fa9ad75..d877f1027c09e 100644
--- a/ui/Makefile
+++ b/ui/Makefile
@@ -58,7 +58,6 @@ julia_res.o: $(JULIAHOME)/contrib/windows/julia.rc
 	$(CROSS_COMPILE)windres $< -O coff -o $@ -DJLVER=$$JLVERi -DJLVER_STR=\\\"$$JLVER\\\"
 $(build_bindir)/julia$(EXE): julia_res.o
 $(build_bindir)/julia-debug$(EXE): julia_res.o
-JLDFLAGS += julia_res.o
 endif
 endif