[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:

I spot checked two other unit tests that have custom mains, and they don't do anything special:
1. llvm-cfi-verify [main](https://github.com/llvm/llvm-project/blob/main/llvm/unittests/tools/llvm-cfi-verify/FileAnalysis.cpp#L1096) , [cmake](https://github.com/llvm/llvm-project/blob/main/llvm/unittests/tools/llvm-cfi-verify/CMakeLists.txt#L14)
2. LiveIntervalTest [main](https://github.com/llvm/llvm-project/blob/main/llvm/unittests/MI/LiveIntervalTest.cpp#L933), [cmake](https://github.com/llvm/llvm-project/blob/main/llvm/unittests/MI/CMakeLists.txt#L13)

I think archive semantics are pretty portable between platforms, so I think this just works. The sources used to build the unit test executable override the main provided by the gtest library.

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