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

[kadir çetinkaya 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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kadircet wrote:

i don't feel great about relying on linking order and linker not loading llvm_gtest_main solely because it wasn't referenced, but I guess that's a theoretical concern that won't matter much in practice (since `llvm_gtest_main` doesn't really define symbols apart from `TestMainArgv0`, at least yet). so leaving this up to you.

but can we at least leave a comment here, mentioning that we're also linking against `llvm_gtest_main` to make it easier for people to investigate if they encounter any such issues?

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