From 957a5ae56038517316f66777d8dc5f090f15c214 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alex=20R=C3=B8nne=20Petersen?= <alex@alexrp.com>
Date: Thu, 3 Apr 2025 07:24:03 +0200
Subject: [PATCH] cmake: Pass -fno-sanitize=undefined when building zig2.

We build zig2.c and compiler_rt.c with -O0 but then proceed to link with -O3.
So zig2.o and compiler_rt.o will have references to ubsan-rt symbols, but the
-O3 causes the compiler to not link ubsan-rt. We don't actually need the safety
here, so just explicitly disable ubsan.
---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e692027173..1b7a5779eb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -809,7 +809,7 @@ if(MSVC)
 else()
   set(ZIG_WASM2C_COMPILE_FLAGS "-std=c99 -O2")
   set(ZIG1_COMPILE_FLAGS "-std=c99 -Os")
-  set(ZIG2_COMPILE_FLAGS "-std=c99 -O0 -fno-stack-protector")
+  set(ZIG2_COMPILE_FLAGS "-std=c99 -O0 -fno-sanitize=undefined -fno-stack-protector")
   if(APPLE)
     set(ZIG2_LINK_FLAGS "-Wl,-stack_size,0x10000000")
   elseif(MINGW)