================
@@ -1304,6 +1304,27 @@ if (LLVM_BUILD_INSTRUMENTED AND 
LLVM_BUILD_INSTRUMENTED_COVERAGE)
   message(FATAL_ERROR "LLVM_BUILD_INSTRUMENTED and 
LLVM_BUILD_INSTRUMENTED_COVERAGE cannot both be specified")
 endif()
 
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND NOT DEFINED 
CMAKE_DISABLE_PRECOMPILE_HEADERS)
+  # Pre-compiled headers with GCC (tested versions 14+15) provide very little
+  # compile-time improvements, but substantially increase the build dir size.
+  # Therefore, disable PCH with GCC by default.
+  message(NOTICE "Precompiled headers are disabled by default with GCC. "
+    "Pass -DCMAKE_DISABLE_PRECOMPILE_HEADERS=OFF to override.")
+  set(CMAKE_DISABLE_PRECOMPILE_HEADERS ON)
+endif()
+if(NOT CMAKE_DISABLE_PRECOMPILE_HEADERS)
+  message(STATUS "Precompiled headers enabled.")
+  if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    # Clang requires this flag in order for precompiled headers to work with 
ccache
----------------
kuhar wrote:

```suggestion
    # Clang requires this flag in order for precompiled headers to work with 
ccache.
```

https://github.com/llvm/llvm-project/pull/176420
_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to