An earlier version of this was posted as:
"[PATCH 2/5] gcc: configure and Makefile changes needed by jit"
https://gcc.gnu.org/ml/gcc-patches/2014-10/msg01169.html
Since then, I've eliminated the gcc_version, bindir, and pkgconfigdir
additions, and added the FULL_DRIVER_NAME variable and symlink, to
avoid the need to install when running the jit testsuite.
gcc/ChangeLog:
* Makefile.in (doc_build_sys): New variable, set to "sphinx" if
sphinx is installed, falling back to "texinfo" otherwise.
(FULL_DRIVER_NAME): New variable, adapted from the
install-driver target. New target, a symlink within the builddir,
linked to "xgcc", for use when running the JIT library from the
builddir.
(MOSTLYCLEANFILES): Add FULL_DRIVER_NAME.
(install-driver): Use $(FULL_DRIVER_NAME) rather than spelling it
out.
* configure.ac (doc_build_sys): New variable, set to "sphinx" if
sphinx is installed, falling back to "texinfo" otherwise.
(GCC_DRIVER_NAME): Generate a gcc-driver-name.h file containing
GCC_DRIVER_NAME for the benefit of jit/internal-api.c.
* configure: Regenerate.