Make UTIL_countPhysicalCores() work under Cygwin (#1941)

Cygwin currently uses the fallback implementation which just returns 1 every time,
which leads to bad performance when zstd is called with -T0 for example.

Instead use the POSIX implementation used for the BSDs which works just fine under Cygwin.

Tested under Cygwin and MSYS2.

diff --git a/programs/util.c b/programs/util.c
index 51d848018a6837afc4ed351f993757ee05f2b952..399507c2aab5a16e214e005b4d8e3b41c4d86e63 100644 (file)
--- a/programs/util.c
+++ b/programs/util.c
@@ -903,7 +903,7 @@ int UTIL_countPhysicalCores(void)
     return numPhysicalCores;
 }
 
-#elif defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
+#elif defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__CYGWIN__)
 
 /* Use POSIX sysconf
  * see: man 3 sysconf */