Disable local runtimes

Author: tstellar

clang/cmake/caches/Release.cmake

@@ -44,6 +44,16 @@ set(LLVM_RELEASE_ENABLE_LTO THIN CACHE STRING "")
 set(LLVM_RELEASE_ENABLE_PGO ON CACHE BOOL "")
 set(LLVM_RELEASE_ENABLE_RUNTIMES ${DEFAULT_RUNTIMES} CACHE STRING "")
 set(LLVM_RELEASE_ENABLE_PROJECTS ${DEFAULT_PROJECTS} CACHE STRING "")
+
+if(${CMAKE_HOST_SYSTEM_NAME} MATCHES "Darwin")
+  # Don't link against the just built runtimes due to:
+  # https://github.com/llvm/llvm-project/issues/77653
+  set(DEFAULT_LINK_LOCAL_RUNTIMES OFF)
+else()
+  set(DEFAULT_LINK_LOCAL_RUNTIMES ON)
+endif()
+set(LLVM_RELEASE_LINK_LOCAL_RUNTIMES ${DEFAULT_LINK_LOCAL_RUNTIMES} CACHE BOOL "")
+
 # Note we don't need to add install here, since it is one of the pre-defined
 # steps.
 set(LLVM_RELEASE_FINAL_STAGE_TARGETS "clang;package;check-all;check-llvm;check-clang" CACHE STRING "")
@@ -55,8 +65,12 @@ set(CLANG_ENABLE_BOOTSTRAP ON CACHE BOOL "")
 
 set(STAGE1_PROJECTS "clang")
 
+# Need to build compiler-rt in order to use PGO for later stages.
+set(STAGE1_RUNTIMES "compiler-rt")
 # Build all runtimes so we can statically link them into the stage2 compiler.
-set(STAGE1_RUNTIMES "compiler-rt;libcxx;libcxxabi;libunwind")
+if(DEFAULT_LINK_LOCAL_RUNTIMES)
+  list(APPEND STAGE1_RUNTIMES "libcxx;libcxxabi;libunwind")
+endif()
 
 if (LLVM_RELEASE_ENABLE_PGO)
   list(APPEND STAGE1_PROJECTS "lld")
@@ -118,11 +132,13 @@ set_instrument_and_final_stage_var(LLVM_ENABLE_LTO "${LLVM_RELEASE_ENABLE_LTO}"
 if (LLVM_RELEASE_ENABLE_LTO)
   set_instrument_and_final_stage_var(LLVM_ENABLE_LLD "ON" BOOL)
 endif()
-set_instrument_and_final_stage_var(LLVM_ENABLE_LIBCXX "ON" BOOL)
-set_instrument_and_final_stage_var(LLVM_STATIC_LINK_CXX_STDLIB "ON" BOOL)
-set(RELEASE_LINKER_FLAGS "-rtlib=compiler-rt --unwindlib=libunwind")
-if(NOT ${CMAKE_HOST_SYSTEM_NAME} MATCHES "Darwin")
-  set(RELEASE_LINKER_FLAGS "${RELEASE_LINKER_FLAGS} -static-libgcc")
+if(DEFAULT_LINK_LOCAL_RUNTIMES)
+  set_instrument_and_final_stage_var(LLVM_ENABLE_LIBCXX "ON" BOOL)
+  set_instrument_and_final_stage_var(LLVM_STATIC_LINK_CXX_STDLIB "ON" BOOL)
+  set(RELEASE_LINKER_FLAGS "-rtlib=compiler-rt --unwindlib=libunwind")
+  if(NOT ${CMAKE_HOST_SYSTEM_NAME} MATCHES "Darwin")
+    set(RELEASE_LINKER_FLAGS "${RELEASE_LINKER_FLAGS} -static-libgcc")
+  endif()
 endif()
 
 # Set flags for bolt