improve the libc of wasm32-freestanding target #2512
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* introduce wasm32-freestanding-musl .h files to fix conflicts with stddef.h and errno.h * fix an issue with zig build system regarding installation of webassembly libraries * add implementations to zig's libc: - strcmp - strncmp - strerror - strlen See #514
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| #ifndef __cplusplus | ||
| #if defined(__NEED_wchar_t) && !defined(__DEFINED_wchar_t) | ||
| typedef int wchar_t; |
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I think musl expects us to pass -fno-signed-wchar to the compiler @richfelker could you confirm?
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Rich's profile says "I don't really use or prefer to use github." - I think we should respect that preference by asking questions in #musl IRC channel
| return std.mem.len(u8, s); | ||
| } | ||
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| extern fn strncmp(_l: [*]const u8, _r: [*]const u8, _n: usize) c_int { |
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Could implement as:
return switch(std.mem.compare(u8, s1[0..n], s2[0..n])) {
.LessThan: -1,
.Equal: 0,
.GreaterThan: 1
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that will be an out of bounds index if n is bigger than strlen(s1) or strlen(s2)
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| test "strncmp" { | ||
| std.testing.expect(strncmp(c"a", c"b", 1) == -1); |
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use expectEqual for better errors :)
| @@ -6059,6 +6059,8 @@ set(ZIG_LIBC_FILES | |||
| "include/x86_64-linux-musl/bits/stat.h" | |||
| "include/x86_64-linux-musl/bits/syscall.h" | |||
| "include/x86_64-linux-musl/bits/user.h" | |||
| "include/wasm32-freestanding-musl/bits/alltypes.h" | |||
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Should we have created libc/musl/arch/wasm32/bits/alltypes.h.in instead?
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I'm not sure why we even have those .in files; it might be a mistake.
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Want to make an issue to follow that up?
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Landed in 01a4897 |
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This was apparently blocking Lua for WebAssembly. WASM is picking up mainstream use as a scripting platform for games, and Lua is likely the most popular scripting language used in gamedev. If anyone is interested in picking up the ‘using zig to build lua for webassembly’ thread, a lot of game developers would pay close attention. |
conflicts with stddef.h and errno.h
webassembly libraries
See #514