Windows/Path.inc: [PR6270] PathV1::makeUnique(): Give arbitrary initial seed for workaround.
FIXME: We should use sys::fs::unique_file() in future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127723 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Windows/Path.inc b/lib/Support/Windows/Path.inc
index f4b7cec..42a92f9 100644
--- a/lib/Support/Windows/Path.inc
+++ b/lib/Support/Windows/Path.inc
@@ -882,7 +882,17 @@
// Find a numeric suffix that isn't used by an existing file. Assume there
// won't be more than 1 million files with the same prefix. Probably a safe
// bet.
- static unsigned FCounter = 0;
+ static int FCounter = -1;
+ if (FCounter < 0) {
+ // Give arbitrary initial seed.
+ // FIXME: We should use sys::fs::unique_file() in future.
+ LARGE_INTEGER cnt64;
+ DWORD x = GetCurrentProcessId();
+ x = (x << 16) | (x >> 16);
+ if (QueryPerformanceCounter(&cnt64)) // RDTSC
+ x ^= cnt64.HighPart ^ cnt64.LowPart;
+ FCounter = x % 1000000;
+ }
do {
sprintf(FNBuffer+offset, "-%06u", FCounter);
if (++FCounter > 999999)