Merge pull request #2327 from ben-clayton/fix-pch

Use CMake's builtin functionality for pre-compiled headers
diff --git a/.gitignore b/.gitignore
index a1fe394..790b880 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,9 +2,12 @@
 *.a
 *.so
 *.exe
+.vscode/
 tags
 TAGS
+bazel-*
 build/
 Test/localResults/
 External/googletest
 External/spirv-tools
+out/
diff --git a/BUILD.gn b/BUILD.gn
index 46c4b28..4743753 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -47,6 +47,9 @@
 }
 
 spirv_tools_dir = glslang_spirv_tools_dir
+if (!defined(glslang_angle)) {
+  glslang_angle = false
+}
 
 config("glslang_public") {
   include_dirs = [ "." ]