On darwin (powerpc only at present, but potentially i686 too) we use "-
mdynamic-no-pic" to build the compiler.
config/mh-ppc-darwin:
# The -mdynamic-no-pic ensures that the compiler executable is built
without
# position-independent-code -- the usual default on Darwin. This fix
speeds
# compiles by 3-5%.
BOOT_CFLAGS += -mdynamic-no-pic
====
This is fine until we try to build plugins.
plugins need fPIC which is overridden by mdynamic-no-pic (with a
warning message emitted).
This means that the autoconfigury machinery defaults to deciding that
ppc can't do plugins.
one cannot force the issue with --enable-plugins.
I've proved to myself that ppc makes and runs the plugins code
perfectly OK (by hacking mh-ppc-darwin off).
=====
However trying to find where exactly I need to patch the autoconfigury
bits is proving more tricky - and I'd welcome some comments;
firstly:
in gcc/configure.ac:
# Check that we can build shared objects with -fPIC -shared
saved_LDFLAGS="$LDFLAGS"
case "${host}" in
*-*-darwin*)
LDFLAGS="$LDFLAGS -fPIC -shared -undefined dynamic_lookup"
;;
*)
LDFLAGS="$LDFLAGS -fPIC -shared"
;;
esac
AC_MSG_CHECKING([for -fPIC -shared])
.. this seems a bit strange : -fPIC is not a ld flag...
maybe something like:
# Check that we can build shared objects with -fPIC -shared
saved_LDFLAGS="$LDFLAGS"
saved_CFLAGS="$CFLAGS"
case "${host}" in
*-*-darwin*)
CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g`
CFLAGS="$CFLAGS -fPIC"
LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup"
;;
*)
CFLAGS="$CFLAGS -fPIC"
LDFLAGS="$LDFLAGS -shared"
;;
esac
AC_MSG_CHECKING([for -fPIC -shared])
===
then Makefile.in has:
PLUGINCFLAGS = @CFLAGS@
I wonder if we need to propagate a PLUGINCFLAGS ?
or put some target-specific stuff there too .. ?
===
Are there any other places I need to look?
(I've only achieved partial success with the changes above ).
cheers,
Iain
