So there's two issues: First of all, on amd64:
g++ -std=c++0x -dM -E - < /dev/null | grep linux cc1: warning: command line option "-std=c++0x" is valid for C++/ObjC++ but not for C #define __linux 1 #define __linux__ 1 #define __gnu_linux__ 1 #define linux 1 Note the warning? That means the -std=c++0x option is effectively ignored. When you add e.g. -x c++, you'll get instead: g++ -std=c++0x -dM -x c++ -E - < /dev/null | grep linux #define __linux 1 #define __linux__ 1 #define __gnu_linux__ 1 Which is how it should be; in "standard" mode, "linux" is an identifier reserved to user code and must not be pre-defined. However, __linux *should* be predefined. The second issue is that on rs6000, the linux macros are defined in a way that's different than on other platforms. This has the effect that even though we get the warning, the std=c++0x option is still considered to be in effect for the preprocessor defines. In addition, due to the bug you mention above, __linux is only defined in non-standard mode instead of always ... However, given that this has been that way (unfortunately) on rs6000 forever, it is probably best not to rely on the presence of __linux in standard mode, and use __linux__ instead. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1349907 Title: gcc, powerpc with C++11 standard does not define __linux To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gcc-4.9/+bug/1349907/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
