Add Clang static analyzer to Clang toolchain defs in GN

build/toolchain/gcc_toolchain.gni

Index: build/toolchain/gcc_toolchain.gni
diff --git a/build/toolchain/gcc_toolchain.gni b/build/toolchain/gcc_toolchain.gni
index 7ee2b6ad25e011bdbba41a6f11e9e7145204771d..0c5fda26e678d50491cef9afa879349095d64f5c 100644
--- a/build/toolchain/gcc_toolchain.gni
+++ b/build/toolchain/gcc_toolchain.gni
@@ -8,6 +8,7 @@ import("//build/config/nacl/config.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/v8_target_cpu.gni")
 import("//build/toolchain/cc_wrapper.gni")
+import("//build/toolchain/clang_static_analyzer.gni")
 import("//build/toolchain/goma.gni")
 import("//build/toolchain/toolchain.gni")
 
@@ -487,6 +488,21 @@ template("clang_toolchain") {
     cxx = "$prefix/clang++"
     ld = cxx
 
+    if (use_clang_static_analyzer) {
+      # Call "ccc-analyzer" or "c++-analyzer" instead of directly calling Clang.
+      # |wrapper_tool| sets the environment variables which are read by the
+      # analyzer tools.
+      analyzer_wrapper =
+          rebase_path("//build/toolchain/clang_static_analyzer_wrapper.py",
+                      root_build_dir)
+      cc = analyzer_wrapper + " --clang-cc-path=${cc} --analyzer=" + rebase_path(
+               "//third_party/llvm/tools/clang/tools/scan-build/libexec/ccc-analyzer",

[Nico, 2017/01/11 20:20:06]

We shouldn't check in stuff referring to third_party/llvm. That will make people
think they should have that, and almost everyone shouldn't have that. Can we
DEPS in just the scan-build scripts somewhere and refer to that?

[Kevin M, 2017/01/18 23:04:29]

Done! third_party/scan-build

+               root_build_dir)
+      cxx = analyzer_wrapper + " --clang-cxx-path=${cxx} --analyzer=" + rebase_path(
+                "//third_party/llvm/tools/clang/tools/scan-build/libexec/c++-analyzer",
+                root_build_dir)
+    }
+
     readelf = "${toolprefix}readelf"
     ar = "${toolprefix}ar"
     nm = "${toolprefix}nm"