[Modules] Recreate file manager for ftime-trace when compiling a module

Close https://github.com/llvm/llvm-project/issues/60544.

The root cause for the issue is that when we compile a module unit, the
file manager (and proprocessor and source manager) are owned by AST
instead of the compilaton instance. So the file manager may be invalid
when we want to create a time-report file for -ftime-trace when we are
compiling a module unit.

This patch tries to recreate the file manager for -ftime-trace if we
find the file manager is not valid.

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index ecc1c4c..9c79e85 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -851,6 +851,9 @@ CompilerInstance::createOutputFileImpl(StringRef OutputPath, bool Binary,
   // relative to that.
   std::optional<SmallString<128>> AbsPath;
   if (OutputPath != "-" && !llvm::sys::path::is_absolute(OutputPath)) {
+    assert(hasFileManager() &&
+           "File Manager is required to fix up relative path.\n");
+
     AbsPath.emplace(OutputPath);
     FileMgr->FixupRelativePath(*AbsPath);
     OutputPath = *AbsPath;