new gcc wrapper, entirely specfile based

the _concept_ of this wrapper has been tested extensively, but the
integration with the build/install system, and using a persistent
specfile rather than one generated at build-time, have not been
heavily tested and may need minor tweaks.

this approach should be a lot more robust (and easier to improve) than
writing a shell script that's responsible for trying to mimic gcc's
logic about whether it's compiling or linking, building shared libs or
executable files, etc. it's also lighter weight and should result in
mildly faster builds when using the wrapper.

4 files changed, 47 insertions, 63 deletions

diff --git a/.gitignore b/.gitignore
index c1a6cd51..455e3580 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ arch/*/bits/alltypes.h
 config.mak
 include/bits
 tools/musl-gcc
+lib/musl-gcc.specs
diff --git a/Makefile b/Makefile
index 7906c52f..72b640a4 100644
--- a/Makefile
+++ b/Makefile
@@ -36,7 +36,8 @@ EMPTY_LIBS = $(EMPTY_LIB_NAMES:%=lib/lib%.a)
 CRT_LIBS = lib/crt1.o lib/crti.o lib/crtn.o
 STATIC_LIBS = lib/libc.a $(EMPTY_LIBS)
 SHARED_LIBS = lib/libc.so
-ALL_LIBS = $(CRT_LIBS) $(STATIC_LIBS) $(SHARED_LIBS)
+TOOL_LIBS = lib/musl-gcc.specs
+ALL_LIBS = $(CRT_LIBS) $(STATIC_LIBS) $(SHARED_LIBS) $(TOOL_LIBS)
 ALL_TOOLS = tools/musl-gcc
 
 LDSO_PATHNAME = $(syslibdir)/ld-musl-$(ARCH).so.1
@@ -93,8 +94,11 @@ $(EMPTY_LIBS):
 lib/%.o: crt/%.o
 	cp $< $@
 
-tools/musl-gcc: tools/gen-musl-gcc.sh config.mak
-	sh $< "$(prefix)" "$(LDSO_PATHNAME)" > $@ || { rm -f $@ ; exit 1 ; }
+lib/musl-gcc.specs: tools/musl-gcc.specs.sh config.mak
+	sh $< "$(includedir)" "$(libdir)" "$(LDSO_PATHNAME)" > $@
+
+tools/musl-gcc: config.mak
+	printf '#!/bin/sh\nexec gcc "$$@" -specs "%s/musl-gcc.specs"\n' "$(libdir)" > $@
 	chmod +x $@
 
 $(DESTDIR)$(bindir)/%: tools/%
diff --git a/tools/gen-musl-gcc.sh b/tools/gen-musl-gcc.sh
deleted file mode 100644
index 7b80fda6..00000000
--- a/tools/gen-musl-gcc.sh
+++ /dev/null
@@ -1,60 +0,0 @@
-#!/bin/sh
-
-printf '#!/bin/sh\n\nlibc_prefix="%s"\nldso_pathname="%s"\n' "$1" "$2"
-
-cat <<"EOF"
-gcc=gcc
-libc_lib=$libc_prefix/lib
-libc_inc=$libc_prefix/include
-libc_crt="$libc_lib/crt1.o"
-libc_start="$libc_lib/crti.o"
-libc_end="$libc_lib/crtn.o"
-
-gcc_inc=$libc_inc
-libgcc="$("$gcc" -print-file-name=libgcc.a)"
-libgcc=${libgcc%/libgcc.a}
-
-gccver=${libgcc##*/}
-gcctarget=${libgcc%/*}
-gcctarget=${gcctarget##*/}
-
-case "$gccver" in
-[0123].*|4.[01]*) ;;
-*) nosp=-fno-stack-protector ;;
-esac
-
-[ "x$1" = "x-V" ] && { printf "%s: -V not supported\n" "$0" ; exit 1 ; }
-
-for i ; do
-case "$skip$i" in
--I|-L) skip=--- ; continue ;;
--[cSE]|-M*) nolink=1 ;;
--shared|-nostartfiles|-nostdlib) nocrt=1 ;;
--*) ;;
-*) havefile=1 ;;
-esac
-skip=
-done
-
-[ "$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 "$tmp_specs"
-set -- -specs=/proc/self/fd/3 "$@" \
-  -Wl,--as-needed -Wl,--start-group -lc -lgcc -lgcc_eh -Wl,--end-group \
-  -Wl,-dynamic-linker,"$ldso_pathname" -Wl,-nostdlib
-}
-
-set -- -nostdinc -nostdlib $nosp \
-  -isystem "$libc_inc" -isystem "$gcc_inc" "$@" \
-  -L"$libc_lib" -L"$libgcc"
-
-exec "$gcc" "$@"
-EOF
diff --git a/tools/musl-gcc.specs.sh b/tools/musl-gcc.specs.sh
new file mode 100644
index 00000000..30b2676d
--- /dev/null
+++ b/tools/musl-gcc.specs.sh
@@ -0,0 +1,39 @@
+incdir=$1
+libdir=$2
+ldso=$3
+cat <<EOF
+%rename cpp_options old_cpp_options
+
+*cpp_options:
+-nostdinc -isystem $incdir %(old_cpp_options)
+
+*cc1:
+%(cc1_cpu) -nostdinc -isystem $incdir 
+
+*link_libgcc:
+-L$libdir
+
+*libgcc:
+libgcc.a%s %:if-exists(libgcc_eh.a%s)
+
+*startfile:
+%{!shared: $libdir/crt1.o} $libdir/crti.o %{shared|pie:crtbeginS.o%s;:crtbegin.o%s}
+
+*endfile:
+%{shared|pie:crtendS.o%s;:crtend.o%s} $libdir/crtn.o
+
+%rename link old_link
+
+*link:
+%(old_link) -dynamic-linker $ldso -nostdlib
+
+*esp_link:
+
+
+*esp_options:
+
+
+*esp_cpp_options:
+
+
+EOF