When I issue a command like (for example) make -j 4, I get the following error:
warning: jobserver unavailable: using -j1. Add `+' to parent make rule
I am using the developer toolkit from Scientific Linux 6 under RHEL6:
$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-2/root/usr/libexec/gcc/x86_64-redhat-linux/4.8.2/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/opt/rh/devtoolset-2/root/usr --mandir=/opt/rh/devtoolset-2/root/usr/share/man --infodir=/opt/rh/devtoolset-2/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --enable-languages=c,c++,fortran,lto --enable-plugin --with-linker-hash-style=gnu --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.8.2-20140120/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.2-20140120/obj-x86_64-redhat-linux/cloog-install --with-mpc=/builddir/build/BUILD/gcc-4.8.2-20140120/obj-x86_64-redhat-linux/mpc-install --with-tune=generic --with-arch_32=i686 --build=x86_64-redhat-linux
Thread model: posix
gcc version 4.8.2 20140120 (Red Hat 4.8.2-15) (GCC)
I have libmpc 0.8.3 installed:
$ rpm -qa | grep mpc
libmpcdec-1.2.6-6.1.el6.x86_64
libmpc-0.8-3.el6.x86_64
Is there a way to troubleshoot my project's makefile or gcc to determine what is causing the warning and fix it? I do not seem to need the + symbol added to rules when building from OS X via Clang/LLVM. Google searches on the warning text are not returning much information that is apparently useful.
make, which is an entirely separate program. The information we need to see is what command in the makefile is causing that warning to be generated: it will be a recursive invocation ofmakeitself. Assuming you're using GNU make on both OSX and Linux, and you're invoking both versions with the same-jflag, and the makefiles you're using to build are the same, I don't know why it would be that it works on one system but not the other. I assume you're using the same shell on both (notcshfor example), etc.make3.81 andbashon both the RHEL6 and OS X 10.9.2 systems. One line that appears to be related to the issue is where I make a staticbzip2library:cd third-party/bzip2-1.0.6 && make libbz2.a && cd /foo/bar && rm -f bzip2 && ln -s bzip2-1.0.6 third-party/bzip2I have a couple other third-party libraries that I build into static libraries, which also show the same warning message.