On 05-03-2014 08:25:38 +0100, Stefan Manegold wrote:

Changeset: a06afa30eeea for MonetDB URL: http://dev.monetdb.org/hg/MonetDB?cmd=changeset;node=a06afa30eeea Modified Files: configure.ag Branch: Jan2014 Log Message:

configure.ag: with clang, disable -pthread as compiler option (but keep it as linker option)

Also clang 3.3 on fedora 20 appears to work fine without -pthread as compiler option (but requires it as linker option).

from man gcc:

-pthread Adds support for multithreading with the pthreads library. This option sets flags for both the preprocessor and linker.

This is typically something like _REENTRANT.

On Mountain Lion, gcc/clang would set _REENTRANT. Same for CentOS 6.

% /usr/bin/gcc -dumpspecs | grep pthread %{static:%{!dynamic:-D__STATIC__}}%{!static:-D__DYNAMIC__} %%{pthread:-D_REENTRANT}

What I can imagine here, is that because clang on Mavericks now defaults to C99 mode (instead of gnu89 mode gcc defaults to) you get different defines and behaviour, possibly including _REENTRANT. A preprocessor check would have to give some facts around that.

Fabian