[libclc] [libclc] Change SPIR-V build flag from -O0 to -disable-llvm-passes (PR #202891)

[Matt Arsenault via cfe-commits]

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@@ -145,7 +145,7 @@ if(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
   if(LIBCLC_TARGET_OS STREQUAL vulkan)
     list(APPEND target_compile_flags -Wno-unknown-assumption -U__opencl_c_int64)
   else()
-    list(APPEND target_compile_flags -O0 -finline-hint-functions)
+    list(APPEND target_compile_flags "SHELL:-Xclang -disable-llvm-passes")
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arsenm wrote:

This shouldn't really be using a cc1 debug flag. -O0 should still run mandatory passes. If you want to change something here it should be in the spirv pass configuration 

https://github.com/llvm/llvm-project/pull/202891