[llvm] a514ce4 - [gn] Add clang_static_plugin_sources to link out-of-tree plugins into clang (#226381)

[via llvm-commits]

Author: Nico Weber
Date: 2026-09-25T08:06:19-07:00
New Revision: a514ce406f06bfbebeb5d8d9bc76e9cc5ec6a92b

URL: https://github.com/llvm/llvm-project/commit/a514ce406f06bfbebeb5d8d9bc76e9cc5ec6a92b
DIFF: https://github.com/llvm/llvm-project/commit/a514ce406f06bfbebeb5d8d9bc76e9cc5ec6a92b.diff

LOG: [gn] Add clang_static_plugin_sources to link out-of-tree plugins into clang (#226381)

This is useful for testing and profiling e.g. Chromium's clang plugins
without having to export symbols from the clang binary.

    # args.gn
    clang_static_plugin_sources = [

"/path/to/chromium/src/tools/clang/plugins/FindBadConstructsAction.cpp",
      ...
    ]
    clang_static_plugin_include_dirs = [ "/path/to/chromium/src" ]

...or put the above in a gni file and put just `import("plugins.gni")`
in args.gn

No behavior change if the list is empty (the default).

Added: 
    

Modified: 
    llvm/utils/gn/secondary/clang/tools/driver/BUILD.gn

Removed: 
    


################################################################################
diff  --git a/llvm/utils/gn/secondary/clang/tools/driver/BUILD.gn b/llvm/utils/gn/secondary/clang/tools/driver/BUILD.gn
index cd3c64256a3e6..76c6cf4f05624 100644
--- a/llvm/utils/gn/secondary/clang/tools/driver/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang/tools/driver/BUILD.gn
@@ -3,6 +3,16 @@ import("//llvm/utils/gn/build/symlink_or_copy.gni")
 import("//llvm/utils/gn/build/write_cmake_config.gni")
 import("//llvm/version.gni")
 
+declare_args() {
+  # Additional source files to compile into the clang binary.
+  # This is for adding statically linked out-of-tree clang plugins.
+  # Use absolute paths ("/path/to/Plugin.cpp").
+  clang_static_plugin_sources = []
+
+  # Include directories for clang_static_plugin_sources.
+  clang_static_plugin_include_dirs = []
+}
+
 symlinks = [
   # target_name, symlink_target pairs: GN doesn't support '+' in rule names.
   [
@@ -99,5 +109,9 @@ driver_executable("clang") {
     "cc1gen_reproducer_main.cpp",
     "driver.cpp",
   ]
+  if (clang_static_plugin_sources != []) {
+    sources += clang_static_plugin_sources
+    include_dirs = clang_static_plugin_include_dirs
+  }
   needs_posix_utility_signal_handling = true
 }