[libcxx] r174642 - Belt and suspenders when calling sysconf

[Marshall Clow]

Author: marshall
Date: Thu Feb  7 12:48:09 2013
New Revision: 174642

URL: http://llvm.org/viewvc/llvm-project?rev=174642&view=rev
Log:
Belt and suspenders when calling sysconf

Modified:
    libcxx/trunk/src/thread.cpp

Modified: libcxx/trunk/src/thread.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/thread.cpp?rev=174642&r1=174641&r2=174642&view=diff
==============================================================================
--- libcxx/trunk/src/thread.cpp (original)
+++ libcxx/trunk/src/thread.cpp Thu Feb  7 12:48:09 2013
@@ -69,7 +69,9 @@ thread::hardware_concurrency() _NOEXCEPT
     long result = sysconf(_SC_NPROCESSORS_ONLN);
     // sysconf returns -1 if the name is invalid, the option does not exist or
     // does not have a definite limit.
-    if (result == -1)
+    // if sysconf returns some other negative number, we have no idea
+    // what is going on. Default to something safe.
+    if (result < 0)
         return 0;
     return static_cast<unsigned>(result);
 #else  // defined(CTL_HW) && defined(HW_NCPU)