[llvm] [CMake] Options to control generation of reproducers (PR #143037)

[Roland McGrath via llvm-commits]

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@@ -1433,3 +1433,22 @@ if(LLVM_ENABLE_LLVM_LIBC)
     message(WARNING "Unable to link against LLVM libc. LLVM will be built without linking against the LLVM libc overlay.")
   endif()
 endif()
+
+if(LLVM_CRASH_DIAGNOSTICS)
+  string(TOLOWER "${LLVM_CRASH_DIAGNOSTICS}" LLVM_CRASH_DIAGNOSTICS)
+  check_c_compiler_flag("-fcrash-diagnostics=${LLVM_CRASH_DIAGNOSTICS}" SUPPORTS_FCRASH_DIAGNOSTICS)
+  append_if(SUPPORTS_FCRASH_DIAGNOSTICS "-fcrash-diagnostics=${LLVM_CRASH_DIAGNOSTICS}"
+    CMAKE_C_FLAGS CMAKE_CXX_FLAGS CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
+endif()
+
+if(LLVM_CRASH_DIAGNOSTICS_DIR)
+  check_c_compiler_flag("-fcrash-diagnostics-dir=foo" SUPPORTS_FCRASH_DIAGNOSTICS_DIR)
+  append_if(SUPPORTS_FCRASH_DIAGNOSTICS_DIR "-fcrash-diagnostics-dir=${LLVM_CRASH_DIAGNOSTICS_DIR}"
+    CMAKE_C_FLAGS CMAKE_CXX_FLAGS CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
+endif()
+
+if(LLVM_ERROR_REPRODUCERS)
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frobtech wrote:

Can we make this a string-valued cmake option so that setting `=always` (or other new modes that might come along) doesn't require fresh cmake plumbing?

https://github.com/llvm/llvm-project/pull/143037