This is essentially a backport of <f52b6c944e> by Eelco Dolstra <eelco.dolstra@logicblox.com>. The use-after-free bug would typically manifest when building with GCC 5.1.
f52b6c944e
* nix/libstore/local-store.cc (LocalStore::getLineFromSubstituter): Flush when the line contains '\r'.
* configure.ac: Call `AC_USE_SYSTEM_EXTENSIONS', and `GUIX_SYSTEM_TYPE'. Add `--with-store-dir' option, and substitute `storedir'. Include `config-daemon.ac'. * config-daemon.ac: New file. * Makefile.am [BUILD_DAEMON]: Include `daemon.am'. * daemon.am: New file. * m4/guix.m4 (GUIX_SYSTEM_TYPE): New macro. * nix/libutil/gcrypt-hash.cc, nix/libutil/gcrypt-hash.hh, nix/libutil/md5.h, nix/libutil/sha1.h, nix/libutil/sha256.h, nix/nix-daemon/guix-daemon.cc, nix/nix-daemon/shared.hh: New files.