Register the __builtin_va_list_type node when we parse it, rather than
waiting until we think we need it: we didn't catch all of the places
where we actually needed it, and we probably wouldn't ever. Fixes a
C++ PCH crasher.

llvm-svn: 115617
diff --git a/clang/test/PCH/va_arg.cpp b/clang/test/PCH/va_arg.cpp
new file mode 100644
index 0000000..7c8dc6b
--- /dev/null
+++ b/clang/test/PCH/va_arg.cpp
@@ -0,0 +1,16 @@
+// Test this without pch.
+// RUN: %clang_cc1 -triple=x86_64-unknown-freebsd7.0 -include %S/Inputs/va_arg.h %s -emit-llvm -o -
+
+// Test with pch.
+// RUN: %clang_cc1 -triple=x86_64-unknown-freebsd7.0 -emit-pch -x c++-header -o %t %S/Inputs/va_arg.h
+// RUN: %clang_cc1 -triple=x86_64-unknown-freebsd7.0 -include-pch %t %s -emit-llvm -o -
+
+typedef __SIZE_TYPE__ size_t;
+
+extern "C" {
+int vsnprintf(char * , size_t, const char * , va_list) ;
+}
+
+void f(char *buffer, unsigned count, const char* format, va_list argptr) {
+  vsnprintf(buffer, count, format, argptr);
+}