Implemented support for Process::GetRandomNumber on Windows.

Patch thanks to Stephan Tolksdorf!

llvm-svn: 200767

2 files changed, 12 insertions, 0 deletions

diff --git a/llvm/lib/Support/Process.cpp b/llvm/lib/Support/Process.cpp
index d5168f03a6d..1360842753d 100644
--- a/llvm/lib/Support/Process.cpp
+++ b/llvm/lib/Support/Process.cpp
@@ -12,6 +12,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Config/config.h"
+#if LLVM_ON_WIN32
+  // This define makes stdlib.h declare the rand_s function.
+#define _CRT_RAND_S
+#include <stdlib.h>
+#endif
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Process.h"
 
diff --git a/llvm/lib/Support/Windows/Process.inc b/llvm/lib/Support/Windows/Process.inc
index 750097eecf4..16e4092e9fa 100644
--- a/llvm/lib/Support/Windows/Process.inc
+++ b/llvm/lib/Support/Windows/Process.inc
@@ -360,3 +360,10 @@ const char *Process::ResetColor() {
   SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE), defaultColors());
   return 0;
 }
+
+unsigned Process::GetRandomNumber() {
+  unsigned int result;
+  const errno_t ec = rand_s(&result);
+  assert(ec == 0 && "rand_s failed");
+  return result;
+}