diff options
Diffstat (limited to 'lib/Support/Windows/Memory.inc')
| -rw-r--r-- | lib/Support/Windows/Memory.inc | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/lib/Support/Windows/Memory.inc b/lib/Support/Windows/Memory.inc index ae8371abf5b3..4b2ff2e2d324 100644 --- a/lib/Support/Windows/Memory.inc +++ b/lib/Support/Windows/Memory.inc @@ -78,7 +78,15 @@ MemoryBlock Memory::allocateMappedMemory(size_t NumBytes, // While we'd be happy to allocate single pages, the Windows allocation // granularity may be larger than a single page (in practice, it is 64K) // so mapping less than that will create an unreachable fragment of memory. - static const size_t Granularity = getAllocationGranularity(); + // Avoid using one-time initialization of static locals here, since they + // aren't thread safe with MSVC. + static volatile size_t GranularityCached; + size_t Granularity = GranularityCached; + if (Granularity == 0) { + Granularity = getAllocationGranularity(); + GranularityCached = Granularity; + } + const size_t NumBlocks = (NumBytes+Granularity-1)/Granularity; uintptr_t Start = NearBlock ? reinterpret_cast<uintptr_t>(NearBlock->base()) + |