[clang] Replace BACKEND_PACKAGE_STRING with LLVM_VERSION_STRING

420d7cc introduced BACKEND_PACKAGE_STRING to
replace `PACKAGE_VERSION` (llvm/Config/config.h) to support standalone builds.
This is used in the output of `clang -cc1 -v`.

Since llvm-config.h is available for both standalone and non-standalone builds,
we can just use `LLVM_VERSION_STRING` from llvm-config.h.

clang/cmake/modules/AddClang.cmake uses `VERSION_STRING "${CLANG_VERSION} (${BACKEND_PACKAGE_STRING})"`.
Just simplify it to `"${CLANG_VERSION}"` so that we can remove the CMake
variable BACKEND_PACKAGE_STRING.

Reviewed By: tstellar

Differential Revision: https://reviews.llvm.org/D136660

clang/CMakeLists.txt

@@ -134,10 +134,6 @@ if(CLANG_BUILT_STANDALONE)
 
     umbrella_lit_testsuite_begin(check-all)
   endif() # LLVM_INCLUDE_TESTS
-
-  set(BACKEND_PACKAGE_STRING "LLVM ${LLVM_PACKAGE_VERSION}")
-else()
-  set(BACKEND_PACKAGE_STRING "${PACKAGE_STRING}")
 endif() # standalone
 
 if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)

clang/cmake/modules/AddClang.cmake

@@ -37,7 +37,7 @@ macro(set_clang_windows_version_resource_properties name)
       VERSION_MAJOR ${CLANG_VERSION_MAJOR}
       VERSION_MINOR ${CLANG_VERSION_MINOR}
       VERSION_PATCHLEVEL ${CLANG_VERSION_PATCHLEVEL}
-      VERSION_STRING "${CLANG_VERSION} (${BACKEND_PACKAGE_STRING})"
+      VERSION_STRING "${CLANG_VERSION}"
       PRODUCT_NAME "clang")
   endif()
 endmacro()

clang/include/clang/Config/config.h.cmake

@@ -60,9 +60,6 @@
 /* Define if we have sys/resource.h (rlimits) */
 #cmakedefine CLANG_HAVE_RLIMITS ${CLANG_HAVE_RLIMITS}
 
-/* The LLVM product name and version */
-#define BACKEND_PACKAGE_STRING "${BACKEND_PACKAGE_STRING}"
-
 /* Linker version detected at compile time. */
 #cmakedefine HOST_LINK_VERSION "${HOST_LINK_VERSION}"
 

clang/lib/Frontend/CompilerInstance.cpp

@@ -41,6 +41,7 @@
 #include "clang/Serialization/InMemoryModuleCache.h"
 #include "llvm/ADT/ScopeExit.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Config/llvm-config.h"
 #include "llvm/Support/BuryPointer.h"
 #include "llvm/Support/CrashRecoveryContext.h"
 #include "llvm/Support/Errc.h"
@@ -1023,9 +1024,9 @@ bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
 
   // Validate/process some options.
   if (getHeaderSearchOpts().Verbose)
-    OS << "clang -cc1 version " CLANG_VERSION_STRING
-       << " based upon " << BACKEND_PACKAGE_STRING
-       << " default target " << llvm::sys::getDefaultTargetTriple() << "\n";
+    OS << "clang -cc1 version " CLANG_VERSION_STRING << " based upon LLVM "
+       << LLVM_VERSION_STRING << " default target "
+       << llvm::sys::getDefaultTargetTriple() << "\n";
 
   if (getCodeGenOpts().TimePasses)
     createFrontendTimer();

llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn

@@ -25,7 +25,6 @@ write_cmake_config("Config") {
     "CLANG_SPAWN_CC1=",
     "DEFAULT_SYSROOT=",
     "GCC_INSTALL_PREFIX=",
-    "BACKEND_PACKAGE_STRING=LLVM ${llvm_version}git",
     "ENABLE_LINKER_BUILD_ID=",
     "ENABLE_X86_RELAX_RELOCATIONS=1",
     "CLANG_ENABLE_OBJC_REWRITER=1",  # FIXME: flag?

llvm/utils/release/bump-version.py

@@ -121,13 +121,6 @@ def process_line(self, line: str) -> str:
                 )
                 if nline != line:
                     break
-        # Match the BACKEND_PACKAGE_STRING in clang/config.h
-        elif "BACKEND_PACKAGE_STRING" in line:
-            nline = re.sub(
-                r'#define BACKEND_PACKAGE_STRING "LLVM ([0-9\.rcgit-]+)"',
-                f'#define BACKEND_PACKAGE_STRING "LLVM {self.version_str()}"',
-                line,
-            )
 
         return nline
 

utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h

@@ -74,9 +74,6 @@
 /* Define if we have sys/resource.h (rlimits) */
 /* CLANG_HAVE_RLIMITS defined conditionally below */
 
-/* The LLVM product name and version */
-#define BACKEND_PACKAGE_STRING "LLVM 16.0.0git"
-
 /* Linker version detected at compile time. */
 /* #undef HOST_LINK_VERSION */