[clang] Add getClangVendor() and use it in CodeGenModule.cpp (#75935)

In 9a38a72f1d482 `ProductId` was assigned from the stringified value of
`CLANG_VENDOR`, if that macro was defined. However, `CLANG_VENDOR` is
supposed to be a string, as it is defined (optionally) as such in the
top-level clang `CMakeLists.txt`.

Move the addition of `-DCLANG_VENDOR` to the compiler flags from
`clang/lib/Basic/CMakeLists.txt` to the top-level `CMakeLists.txt`, so
it is consistent across the whole clang codebase. Then remove the
stringification from `CodeGenModule.cpp`, to make it work correctly.

Fixes:		9a38a72f1d482

1 files changed, 1 insertions, 6 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 7ad26ac..b2e173d0 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -995,12 +995,7 @@ void CodeGenModule::Release() {
                               uint32_t(CLANG_VERSION_MINOR));
     getModule().addModuleFlag(llvm::Module::Warning, "zos_product_patchlevel",
                               uint32_t(CLANG_VERSION_PATCHLEVEL));
-    std::string ProductId;
-#ifdef CLANG_VENDOR
-    ProductId = #CLANG_VENDOR;
-#else
-    ProductId = "clang";
-#endif
+    std::string ProductId = getClangVendor() + "clang";
     getModule().addModuleFlag(llvm::Module::Error, "zos_product_id",
                               llvm::MDString::get(VMContext, ProductId));