diff --git a/GNUmakefile b/GNUmakefile
index 3080cd3..6549099 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -65,7 +65,9 @@ iwyu: clean $(SRC_O) $(TST_O) $(EXAMPLE_O)
 IWYU = include-what-you-use -Xiwyu --no_fwd_decls -Xiwyu --error=1 -Xiwyu --verbose=3
 
 cppcheck: $(SRC_C) $(SRC_CXX) $(INC_H) $(EXAMPLE_C) $(TST_H) $(TST_C)
-	cppcheck $(^) --enable=warning,unusedFunction,performance,portability --suppressions-list=bld/cppcheck.supp --error-exitcode=1 $(CPPFLAGS)
+	# TODO: add --check-level=exhaustive when cppcheck ~2.14 is availble for CI
+	# cppcheck --enable=warning,unusedFunction,performance,portability --check-level=exhaustive --suppressions-list=bld/cppcheck.supp --error-exitcode=1 $(^)
+	cppcheck --enable=warning,unusedFunction,performance,portability --suppressions-list=bld/cppcheck.supp --error-exitcode=1 $(^)
 
 %-vg: VALGRIND = valgrind --error-exitcode=1 --leak-check=full --show-leak-kinds=all --errors-for-leak-kinds=all --gen-suppressions=all --suppressions=bld/vg.supp
 %-vg: % ;
diff --git a/bld/cppcheck.supp b/bld/cppcheck.supp
index 6075d6c..589de9a 100644
--- a/bld/cppcheck.supp
+++ b/bld/cppcheck.supp
@@ -1,3 +1,3 @@
 unusedFunction:lib/col/*c
 unusedFunction:tst/wrap-log.c
-unusedFunction:tst/util.c
+unusedFunction:pro/*h
diff --git a/inc/fs.h b/inc/fs.h
index e3c2ce3..b960bf3 100644
--- a/inc/fs.h
+++ b/inc/fs.h
@@ -2,7 +2,7 @@
 #define FS_H
 
 #include <stdbool.h>
-#include <sys/stat.h>
+#include <sys/types.h>
 
 bool mkdir_p(char *path, mode_t mode);
 
diff --git a/src/fs.c b/src/fs.c
index 95fe89c..88d9635 100644
--- a/src/fs.c
+++ b/src/fs.c
@@ -4,6 +4,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 
 #include "log.h"
 
diff --git a/src/process.c b/src/process.c
index 62b42ff..ec35f3c 100644
--- a/src/process.c
+++ b/src/process.c
@@ -6,6 +6,7 @@
 #include <stdlib.h>
 #include <sys/file.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 
 #include "process.h"
diff --git a/tst/tst-cfg-file.c b/tst/tst-cfg-file.c
index 73cfed1..b94b874 100644
--- a/tst/tst-cfg-file.c
+++ b/tst/tst-cfg-file.c
@@ -8,6 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 
 #include "global.h"
@@ -259,7 +260,7 @@ void cfg_file_write__existing(void **state) {
 
 	FILE *f = fopen(cfg->file_path, "w");
 	assert_non_null(f);
-	assert_int_equal(fclose(f), 0);
+	fclose(f);
 
 	char *expected = strdup("XXXX");
 
diff --git a/tst/tst-fs.c b/tst/tst-fs.c
index 14c06a0..89dca42 100644
--- a/tst/tst-fs.c
+++ b/tst/tst-fs.c
@@ -4,6 +4,7 @@
 #include <cmocka.h>
 #include <errno.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 
 #include "log.h"
diff --git a/tst/tst-layout.c b/tst/tst-layout.c
index 64aae2e..9fc03ca 100644
--- a/tst/tst-layout.c
+++ b/tst/tst-layout.c
@@ -5,7 +5,6 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 #include <wayland-client-protocol.h>
 #include <wayland-util.h>
 
@@ -16,7 +15,6 @@
 #include "log.h"
 #include "mode.h"
 #include "slist.h"
-#include "util.h"
 #include "wlr-output-management-unstable-v1.h"
 
 struct SList *order_heads(struct SList *order_name_desc, struct SList *heads);