Commit Xavier's fix for #6032.

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@13750 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

2 files changed, 7 insertions, 1 deletions

diff --git a/Changes b/Changes
index 018e72f04..698223322 100644
--- a/Changes
+++ b/Changes
@@ -130,6 +130,7 @@ Bug fixes:
 - PR#6010: Big_int.extract_big_int gives wrong results on negative arguments
 - PR#6024: Format syntax for printing @ is incompatible with 3.12.1
 - PR#6001: Reduce the memory used by compiling Camlp4
+- PR#6032: better Random.self_init under Windows
 
 Internals:
 - Moved debugger/envaux.ml to typing/envaux.ml to publish env_of_only_summary
diff --git a/byterun/win32.c b/byterun/win32.c
index 2b4aacced..d807f6900 100644
--- a/byterun/win32.c
+++ b/byterun/win32.c
@@ -469,13 +469,18 @@ int caml_win32_random_seed (intnat data[16])
 {
   /* For better randomness, consider:
      http://msdn.microsoft.com/library/en-us/seccrypto/security/rtlgenrandom.asp
+     http://blogs.msdn.com/b/michael_howard/archive/2005/01/14/353379.aspx
   */
   FILETIME t;
+  LARGE_INTEGER pc;
   GetSystemTimeAsFileTime(&t);
+  QueryPerformanceCounter(&pc);  /* PR#6032 */
   data[0] = t.dwLowDateTime;
   data[1] = t.dwHighDateTime;
   data[2] = GetCurrentProcessId();
-  return 3;
+  data[3] = pc.LowPart;
+  data[4] = pc.HighPart;
+  return 5;
 }