[CrashReproducer] Setup 'use-external-names' in YAML files.

Hide the real paths when rebuilding from VFS by setting up the crash
reproducer to use 'use-external-names' = false. This way we avoid
module redifinition errors and consistently use the same paths against
all modules.

With this change on Darwin we are able to simulate a crash for a simple
application using "Foundation/Foundation.h" (which relies on a bunch of
different frameworks and headers) and successfully rebuild all the
modules by relying solely at the VFS overlay.

llvm-svn: 266234

1 files changed, 4 insertions, 0 deletions

diff --git a/clang/lib/Frontend/ModuleDependencyCollector.cpp b/clang/lib/Frontend/ModuleDependencyCollector.cpp
index 3e6c0d24750..02d3c515ef0 100644
--- a/clang/lib/Frontend/ModuleDependencyCollector.cpp
+++ b/clang/lib/Frontend/ModuleDependencyCollector.cpp
@@ -112,6 +112,10 @@ void ModuleDependencyCollector::writeFileMap() {
   // the sensitivity at the path where the headers all collected to.
   VFSWriter.setCaseSensitivity(isCaseSensitivePath(VFSDir));
 
+  // Do not rely on real path names when executing the crash reproducer scripts
+  // since we only want to actually use the files we have on the VFS cache.
+  VFSWriter.setUseExternalNames(false);
+
   std::error_code EC;
   SmallString<256> YAMLPath = VFSDir;
   llvm::sys::path::append(YAMLPath, "vfs.yaml");