commit b9b9fd4fadc4d4fa0b030941a35011956eafa10b
author peter <peterghost86@gmail.com> Wed Oct 09 09:30:02 2019 -0700
committer Facebook Github Bot <facebook-github-bot@users.noreply.github.com> Wed Oct 09 09:31:23 2019 -0700
tree 52f3faafbeec1a4d0024c52c8bfbed1c6804827e
parent 987e37b9c24ef5c5c92d5eebb6137dd6006f2a0f

Fix the arithmetic overflow issue for MSVC (#27596)

Summary:
Fixes https://github.com/pytorch/pytorch/issues/27568.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27596

Differential Revision: D17831612

Pulled By: ezyang

fbshipit-source-id: eff18095a74b6b82f70ed3f11d201483097205c5

c10/util/llvmMathExtras.h

diff --git a/c10/util/llvmMathExtras.h b/c10/util/llvmMathExtras.h
index 76ae3b2..4cda3cc 100644
--- a/c10/util/llvmMathExtras.h
+++ b/c10/util/llvmMathExtras.h
@@ -388,13 +388,23 @@
    return UINT64_MAX >> (64 - N);
  }
 
+ // Ignore the false warning "Arithmetic overflow" for MSVC
+ #ifdef _MSC_VER
+ # pragma warning(push)
+ # pragma warning(disable : 4146)
+ #endif
+
  /// Gets the minimum value for a N-bit signed integer.
  inline int64_t minIntN(int64_t N) {
    assert(N > 0 && N <= 64 && "integer width out of range");
 
-   return -(UINT64_C(1)<<(N-1));
+   return -(UINT64_C(1) << (N - 1));
  }
 
+ #ifdef _MSC_VER
+ # pragma warning(pop)
+ #endif
+
  /// Gets the maximum value for a N-bit signed integer.
  inline int64_t maxIntN(int64_t N) {
    assert(N > 0 && N <= 64 && "integer width out of range");