Add a driver option -ivfsoverlay

Reads the description of a virtual filesystem from a file and overlays
it over the real file system.

llvm-svn: 202176

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/test/VFS/include-virtual-from-real.c b/clang/test/VFS/include-virtual-from-real.c
new file mode 100644
index 00000000000..c8f6059608d
--- /dev/null
+++ b/clang/test/VFS/include-virtual-from-real.c
@@ -0,0 +1,12 @@
+// RUN: rm -rf %t
+// RUN: mkdir -p %t
+// RUN: echo '#include "not_real.h"' > %t/include_not_real.h
+// RUN: sed -e "s:INPUT_DIR:%S/Inputs:g" -e "s:OUT_DIR:%t:g" %S/Inputs/vfsoverlay.yaml > %t.yaml
+// RUN: %clang_cc1 -Werror -ivfsoverlay %t.yaml -I %t -fsyntax-only %s
+// REQUIRES: shell
+
+#include "include_not_real.h"
+
+void foo() {
+  bar();
+}