[cfe-commits] [PATCH] Fixes tooling segfaults when reusing the stat cache from pch loading in subsequent translation units

[Douglas Gregor]

Sent from my iPhone

On Jul 31, 2012, at 4:58 AM, Manuel Klimek <klimek at google.com> wrote:

> Hi Doug,
> 
> this is hopefully exactly what you proposed in the other thread (not
> unexpectedly, your analysis turned out to be spot on ;)

Looks good, thanks! 

> Thanks!
> /Manuel
> 
> diff --git a/include/clang/Basic/FileManager.h
> b/include/clang/Basic/FileManager.h
> index 930523f..b00f2b7 100644
> --- a/include/clang/Basic/FileManager.h
> +++ b/include/clang/Basic/FileManager.h
> @@ -186,6 +186,9 @@ public:
>   /// \brief Removes the specified FileSystemStatCache object from the manager.
>   void removeStatCache(FileSystemStatCache *statCache);
> 
> +  /// \brief Removes all FileSystemStatCache objects from the manager.
> +  void clearStatCaches();
> +
>   /// \brief Lookup, cache, and verify the specified directory (real or
>   /// virtual).
>   ///
> diff --git a/lib/Basic/FileManager.cpp b/lib/Basic/FileManager.cpp
> index b921f3e..c6b894c 100644
> --- a/lib/Basic/FileManager.cpp
> +++ b/lib/Basic/FileManager.cpp
> @@ -223,6 +223,10 @@ void
> FileManager::removeStatCache(FileSystemStatCache *statCache) {
>   PrevCache->setNextStatCache(statCache->getNextStatCache());
> }
> 
> +void FileManager::clearStatCaches() {
> +  StatCache.reset(0);
> +}
> +
> /// \brief Retrieve the directory that the given file name resides in.
> /// Filename can point to either a real file or a virtual file.
> static const DirectoryEntry *getDirectoryFromFile(FileManager &FileMgr,
> diff --git a/lib/Tooling/Tooling.cpp b/lib/Tooling/Tooling.cpp
> index 5d41172..e93e0c9 100644
> --- a/lib/Tooling/Tooling.cpp
> +++ b/lib/Tooling/Tooling.cpp
> @@ -212,6 +212,7 @@ bool ToolInvocation::runInvocation(
>   const bool Success = Compiler.ExecuteAction(*ScopedToolAction);
> 
>   Compiler.resetAndLeakFileManager();
> +  Files->clearStatCaches();
>   return Success;
> }
> 
> diff --git a/test/Tooling/Inputs/pch-fail.h b/test/Tooling/Inputs/pch-fail.h
> new file mode 100644
> index 0000000..e69de29
> diff --git a/test/Tooling/Inputs/pch.cpp b/test/Tooling/Inputs/pch.cpp
> new file mode 100644
> index 0000000..e69de29
> diff --git a/test/Tooling/Inputs/pch.h b/test/Tooling/Inputs/pch.h
> new file mode 100644
> index 0000000..e69de29
> diff --git a/test/Tooling/pch.cpp b/test/Tooling/pch.cpp
> new file mode 100644
> index 0000000..bfa20d8
> --- /dev/null
> +++ b/test/Tooling/pch.cpp
> @@ -0,0 +1,21 @@
> +// This is a regression test for handling of stat caches within the tooling
> +// infrastructure. This test reproduces the problem under valgrind:
> +
> +// First, create a pch that we can later load. Loading the pch will insert
> +// a stat cache into the FileManager:
> +// RUN: %clang -x c++-header %S/Inputs/pch.h -o %t1
> +
> +// Use the generated pch and enforce a subsequent stat miss by by using
> +// the test file with an unrelated include as second translation unit:
> +// Do not directly pipe into FileCheck, as that would hide errors from
> +// valgrind due to pipefail not being set in lit.
> +// RUN: clang-check "%S/Inputs/pch.cpp" "%s" -- -include-pch %t1 -I
> "%S" -c >%t2 2>&1
> +// RUN: FileCheck %s < %t2
> +
> +#include "Inputs/pch-fail.h"
> +
> +// CHECK: Processing
> +
> +// FIXME: This is incompatible to -fms-compatibility.
> +// XFAIL: win32
> +
> <fix-stat-cache.patch>