diff options
Diffstat (limited to 'lib/LTO/Caching.cpp')
-rw-r--r-- | lib/LTO/Caching.cpp | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/lib/LTO/Caching.cpp b/lib/LTO/Caching.cpp index 1708ab4c5c7..32fdd422187 100644 --- a/lib/LTO/Caching.cpp +++ b/lib/LTO/Caching.cpp @@ -14,9 +14,9 @@ #include "llvm/LTO/Caching.h" #include "llvm/ADT/StringExtras.h" #include "llvm/Support/Errc.h" -#include "llvm/Support/FileSystem.h" #include "llvm/Support/MemoryBuffer.h" #include "llvm/Support/Path.h" +#include "llvm/Support/Process.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; @@ -72,10 +72,23 @@ Expected<NativeObjectCache> lto::localCache(StringRef CacheDirectoryPath, MBOrErr.getError().message() + "\n"); // This is atomic on POSIX systems. - if (auto EC = sys::fs::rename(TempFilename, EntryPath)) + // On Windows, it can fail with permission denied if the destination + // file already exists. Since the existing file should be semantically + // equivalent to the one we are trying to write, we give AddBuffer + // a copy of the bytes we wrote in that case. We do this instead of + // just using the existing file, because the pruner might delete the + // file before we get a chance to use it. + auto EC = sys::fs::rename(TempFilename, EntryPath); + if (EC == errc::permission_denied) { + auto MBCopy = MemoryBuffer::getMemBufferCopy( + (*MBOrErr)->getBuffer(), EntryPath); + MBOrErr = std::move(MBCopy); + sys::fs::remove(TempFilename); + } else if (EC) { report_fatal_error(Twine("Failed to rename temporary file ") + TempFilename + " to " + EntryPath + ": " + EC.message() + "\n"); + } AddBuffer(Task, std::move(*MBOrErr), EntryPath); } |