Enable support for building libgccjit

libgccjit is still under development and, despite its name, may also be used for
ahead-of-time compilation.

Documentation can be found on the gcc website:
https://gcc.gnu.org/onlinedocs/jit/internals/index.html
https://gcc.gnu.org/wiki/JIT

With this change it's possible to enable the building of the libgccjit. It's
enabled as a language (with --enable-languages=jit) even if not a language
frontend at all.

The main changes are related to the requirement of having everything host side
built as Position Independent Code (PIC) with --enable-host-shared. GCC has the
needed logic for building its dependencies (mpc, gmp, mpfr, ...) correctly when
built "in-tree", which is not the case with crosstool-ng (see
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=05048fc29f0)

Signed-off-by: Marc Poulhiès <dkm@kataplop.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/scripts/build/companion_libs/140-mpc.sh b/scripts/build/companion_libs/140-mpc.sh
index 2166ef1b..2bbba2d9 100644
--- a/scripts/build/companion_libs/140-mpc.sh
+++ b/scripts/build/companion_libs/140-mpc.sh
@@ -38,6 +38,11 @@ do_mpc_for_build() {
     mpc_opts+=( "prefix=${CT_BUILDTOOLS_PREFIX_DIR}" )
     mpc_opts+=( "cflags=${CT_CFLAGS_FOR_BUILD}" )
     mpc_opts+=( "ldflags=${CT_LDFLAGS_FOR_BUILD}" )
+
+    if [ "${CT_CC_LANG_JIT}" = "y" ]; then
+        mpc_opts+=("--with-pic")
+    fi
+
     do_mpc_backend "${mpc_opts[@]}"
 
     CT_Popd
@@ -73,11 +78,17 @@ do_mpc_backend() {
     local cflags
     local ldflags
     local arg
+    local -a extra_config
 
     for arg in "$@"; do
         eval "${arg// /\\ }"
     done
 
+    if [ "${CT_CC_LANG_JIT}" = "y" ]; then
+        extra_config+=("--with-pic")
+    fi
+
+
     CT_DoLog EXTRA "Configuring MPC"
 
     CT_DoExecLog CFG                                \
@@ -87,6 +98,7 @@ do_mpc_backend() {
     "${CT_SRC_DIR}/mpc/configure"                   \
         --build=${CT_BUILD}                         \
         --host=${host}                              \
+        "${extra_config[@]}"                        \
         --prefix="${prefix}"                        \
         --with-gmp="${prefix}"                      \
         --with-mpfr="${prefix}"                     \