fix: add -Wno-format to fix GCC builds

Author: not-matthias

.github/workflows/ci.yml

@@ -10,6 +10,7 @@ env:
   COMMON_CFLAGS: >-
     -Wall
     -Werror
+    -Wno-format
     -Wno-format-security
     -Wno-unused-but-set-variable
     -Wno-unused-const-variable

Justfile

@@ -21,12 +21,15 @@ test:
     zig build test --summary all
 
 test-valgrind:
+    #!/usr/bin/env bash
     rm -f /tmp/runner*.fifo
 
-    clang -O3 example/main.c dist/core.c -I includes/ -o clang-main && ./clang-main
+    export CFLAGS="-Wno-error=format -Wno-error=format-security -Wno-format -Wno-format-security"
+
+    clang $CFLAGS -O3 example/main.c dist/core.c -I includes/ -o clang-main && ./clang-main
     valgrind ./clang-main
 
-    gcc -O3 example/main.c dist/core.c -I includes/ -o gcc-main && ./gcc-main
+    gcc $CFLAGS -O3 example/main.c dist/core.c -I includes/ -o gcc-main && ./gcc-main
     valgrind ./gcc-main
 
     rm -rf clang-main gcc-main

src/runner_fifo.zig

@@ -8,6 +8,9 @@ pub const PROTOCOL_VERSION: u64 = 2;
 
 // Note: Using printf to avoid the extra code from std.log/std.debug. Those won't
 // compile because they are internally using syscalls (for Mutexes) which aren't cross-platform.
+//
+// We have to use c_char here, otherwise we redeclare it and cast u8 to char which results in
+// additional warnings (-Wbuiltin-declaration-mismatch and -Wpointer-sign).
 extern "c" fn printf(format: [*c]const c_char, ...) c_int;
 
 pub const RunnerFifo = struct {