make gcc wrapper support -shared correctly

it was previously attempting to link start files as part of shared
objects. this is definitely wrong and depending on the platform and
linker could range from just adding extraneous junk to introducing
textrels to making linking fail entirely.

diff --git a/tools/gen-musl-gcc.sh b/tools/gen-musl-gcc.sh
index 1ef0550f12c45374d77e354cc4e8a882d78cc9a3..edc408466315410a28d3d59637c1f0bd27575ad0 100644 (file)
--- a/tools/gen-musl-gcc.sh
+++ b/tools/gen-musl-gcc.sh
@@ -29,6 +29,7 @@ for i ; do
 case "$skip$i" in
 -I|-L) skip=--- ; continue ;;
 -[cSE]|-M*) nolink=1 ;;
+-shared) nocrt=1 ;;
 -*) ;;
 *) havefile=1 ;;
 esac
@@ -37,13 +38,17 @@ done
 
 [ "$havefile" ] || nolink=1
 
+[ "$nolink" ] && nocrt=1
+
+[ "$nocrt" ] || set -- "$libc_start" "$libc_crt" "$@" "$libc_end" \
+
 [ "$nolink" ] || {
 tmp_specs=$HOME/.specs.tmp.$$
 printf '*link_libgcc:\n\n\n' > "$tmp_specs" || exit 1
 exec 3<"$tmp_specs"
 rm -f "$tmp_specs"
-set -- -specs=/proc/self/fd/3 "$libc_start" "$libc_crt" "$@" "$libc_end" \
-  -Wl,--start-group -lc -lgcc -lgcc_eh -Wl,--end-group \
+set -- -specs=/proc/self/fd/3 "$@" \
+  -Wl,--as-needed -Wl,--start-group -lc -lgcc -lgcc_eh -Wl,--end-group \
   -Wl,-dynamic-linker,"$ldso_pathname" -Wl,-nostdlib
 }