[clang] [clang] Register all LLVM targets in AllClangUnitTest main (PR #144428)

[Reid Kleckner via cfe-commits]

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@@ -117,6 +117,7 @@ get_property(LINK_LIBS GLOBAL PROPERTY CLANG_UNITTEST_LINK_LIBS)
 get_property(LLVM_COMPONENTS GLOBAL PROPERTY CLANG_UNITTEST_LLVM_COMPONENTS)
 add_distinct_clang_unittest(AllClangUnitTests
   ${SRCS}
+  AllClangUnitTests.cpp
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rnk wrote:

Yeah, on second thought, there's a lot more going on in UnitTestMain than I thought. I rewrote this to use a dynamic initializer to register the targets instead. Those will reliably run before test fixtures. The only risk here is that we encounter intialization-order-fiasco issues, but I spot-checked x86, and it seems to be resilient to that... I will test with ASan locally to build confidence, but PTAL at the new approach.

https://github.com/llvm/llvm-project/pull/144428