From ae59a6c13cddac1af498452f3f488dbf28468c95 Mon Sep 17 00:00:00 2001
From: Max Horn <max@quendi.de>
Date: Fri, 4 Mar 2022 12:22:45 +0100
Subject: [PATCH] buildsys: change gac to not use libtool

---
 Makefile.rules      | 76 +++++++++++++++++++++++++++++++++++----------
 cnf/gac.in          | 63 ++++++++++++-------------------------
 configure.ac        |  1 -
 etc/Makefile.gappkg | 22 +++++--------
 4 files changed, 86 insertions(+), 76 deletions(-)

diff --git a/Makefile.rules b/Makefile.rules
index a9c34716f11..477c2e37867 100644
--- a/Makefile.rules
+++ b/Makefile.rules
@@ -207,6 +207,9 @@ endif
 # Finally add user provided CFLAGS
 GAP_CFLAGS += $(CFLAGS)
 
+# Expose all flags to package build systems
+SYSINFO_CFLAGS = $(GAP_CFLAGS)
+
 
 ########################################################################
 # C++ compiler flags
@@ -220,11 +223,15 @@ endif
 # Finally add user provided CXXFLAGS
 GAP_CXXFLAGS += $(CXXFLAGS)
 
+# Expose all flags to package build systems
+SYSINFO_CXXFLAGS = $(GAP_CXXFLAGS)
+
 
 ########################################################################
 # Linker flags
 ########################################################################
 GAP_LDFLAGS = $(ABI_CFLAGS)
+SYSINFO_LDFLAGS = $(ABI_CFLAGS)
 
 # Add flags for dependencies
 GAP_LDFLAGS += $(GMP_LDFLAGS)
@@ -240,10 +247,12 @@ endif
 
 # Finally add user provided flags
 GAP_LDFLAGS += $(LDFLAGS)
+SYSINFO_LDFLAGS += $(LDFLAGS)
 
 
 # libs
 GAP_LIBS =
+SYSINFO_LIBS =
 
 # Add flags for dependencies
 GAP_LIBS += $(GMP_LIBS)
@@ -255,6 +264,46 @@ GAP_LIBS += $(LIBATOMIC_OPS_LIBS)
 
 # Finally add user provided flags
 GAP_LIBS += $(LIBS)
+SYSINFO_LIBS += $(LIBS)
+
+
+########################################################################
+# gac flags
+########################################################################
+
+#
+# Determine flags for building kernel extensions for use in GAC
+#
+# For now we basically support GCC and clang, on Linux/macOS/Windows,
+# and as a side effect also some other systems such as FreeBSD.
+# Support for other compilers or operating systems will require some
+# extra tweaks.
+#
+ifneq (,$(findstring cygwin,$(host_os)))
+  GAC_CFLAGS =
+  GAC_LDFLAGS = -shared -Wl,$(abs_builddir)/bin/$(GAPARCH)/gap.dll
+  # Note: the above won't be correct after "make install"; but then I am not
+  # sure we care about "make install" on Cygwin, so I am not going to work on
+  # this until someone specifically asks for it (and even then I'll require
+  # that person to help test it)
+else
+  ifneq (,$(findstring darwin,$(host_os)))
+    GAC_CFLAGS = -fno-common
+    GAC_LDFLAGS = -bundle -bundle_loader $(SYSINFO_GAP)
+  else
+    GAC_CFLAGS = -fPIC
+    GAC_LDFLAGS = -shared
+  endif
+endif
+
+
+########################################################################
+# additional settings for use in sysinfo.gap
+########################################################################
+
+# paths to gap and gac executable
+SYSINFO_GAP = $(abs_builddir)/gap
+SYSINFO_GAC = $(abs_builddir)/gac
 
 
 ########################################################################
@@ -529,10 +578,8 @@ install-bin: gap
 	echo "$$gap_wrapper" > $(DESTDIR)$(bindir)/gap
 	chmod 0755 $(DESTDIR)$(bindir)/gap
 	
-	# TODO: make gac installable; this requires adjusting path in it, and
-	# installing the libtool script generated by configure somewhere; and then
-	# putting that path to it into gac)
-	#$(INSTALL) gac $(DESTDIR)$(bindir)
+	sed -e "s;@SYSINFO_GAPROOT@;$(libdir)/gap;" < $(srcdir)/cnf/gac.in >  $(DESTDIR)$(bindir)/gac
+	chmod 0755 $(DESTDIR)$(bindir)/gac
 
 install-doc:
 	# TODO: should this depend on the 'doc' target? but that target is phony
@@ -769,16 +816,6 @@ endif
 #
 # regenerate sysinfo.gap if necessary
 #
-
-SYSINFO_GAP = $(abs_builddir)/gap
-SYSINFO_GAC = $(abs_builddir)/gac
-
-SYSINFO_CFLAGS = $(GAP_CFLAGS)
-SYSINFO_CXXFLAGS = $(GAP_CXXFLAGS)
-#SYSINFO_CPPFLAGS is already initialized at this point
-SYSINFO_LDFLAGS = $(GAP_LDFLAGS)
-SYSINFO_LIBS = $(GAP_LIBS)
-
 define sysinfo_gap
 # This file has been generated by the GAP build system,
 # DO NOT EDIT MANUALLY!
@@ -828,7 +865,7 @@ GAP="$(SYSINFO_GAP)"
 # GAC: path to the `gac` executable (may be a shell script)
 GAC="$(SYSINFO_GAC)"
 
-# Build flags for use by `gac` resp. build systems: these correspond to
+# Build flags for use by `gac` resp. package build systems: these correspond to
 # the usual variables as used by e.g. autotools, with the added prefix `GAP_`.
 GAP_CC="$(CC)"
 GAP_CXX="$(CXX)"
@@ -837,6 +874,10 @@ GAP_CXXFLAGS="$(SYSINFO_CXXFLAGS)"
 GAP_CPPFLAGS="$(SYSINFO_CPPFLAGS)"
 GAP_LDFLAGS="$(SYSINFO_LDFLAGS)"
 GAP_LIBS="$(SYSINFO_LIBS)"
+
+# Extra flags for use by `gac`
+GAC_CFLAGS="$(GAC_CFLAGS)"
+GAC_LDFLAGS="$(GAC_LDFLAGS)"
 endef
 export sysinfo_gap
 
@@ -1436,8 +1477,9 @@ doc/make_doc: $(srcdir)/doc/make_doc.in config.status
 CITATION: $(srcdir)/CITATION.in config.status
 	@$(SHELL) ./config.status $@
 
-gac: $(srcdir)/cnf/gac.in config.status
-	@$(SHELL) ./config.status $@
+gac: $(srcdir)/cnf/gac.in
+	sed -e "s;@SYSINFO_GAPROOT@;$(abs_top_builddir);" < $< > $@
+	chmod a+x $@
 
 GNUmakefile: $(srcdir)/GNUmakefile.in config.status
 	$(SHELL) ./config.status $@
diff --git a/cnf/gac.in b/cnf/gac.in
index 92b78135c50..f3e11fd4fe2 100644
--- a/cnf/gac.in
+++ b/cnf/gac.in
@@ -49,34 +49,19 @@
 ##   -k|--gap-compiler
 ##
 
-# absolute path of the directory in which GAP was compiled
-abs_top_builddir="@abs_top_builddir@"
-
-#
-libdir="@libdir@"
-
-# path to the GAP executable
-gap_compiler="${abs_top_builddir}/gap"
-
-libtool="@SHELL@ ${abs_top_builddir}/libtool"
-
-# read sysinfo.gap, which should set GAP_CFLAGS, GAP_CPPFLAGS, etc.
-. "${abs_top_builddir}/sysinfo.gap"
-
-# These three should be filled in by the standard autoconf procedures
-c_compiler="$libtool --mode=compile $GAP_CC"
-cxx_compiler="$libtool --mode=compile $GAP_CXX"
-
-# These will need special care
-c_dyn_linker="$libtool --mode=link $GAP_CC -module -avoid-version -rpath $libdir"
+# read sysinfo.gap, which sets GAP_CFLAGS, GAP_CPPFLAGS, etc.
+. "@SYSINFO_GAPROOT@/sysinfo.gap"
+
+# Extract sysinfo settings...
+gap_compiler="${GAP}"
+c_compiler="${GAP_CC}"
+cxx_compiler="${GAP_CXX}"
+c_dyn_linker="${GAP_CC}"
 c_addlibs=""
 
-SYS_IS_CYGWIN32=@SYS_IS_CYGWIN32@
-if [ X"$SYS_IS_CYGWIN32" = X"yes" ] ; then
-    c_dyn_linker="$c_dyn_linker -no-undefined -version-info 0:0:0"
-    # FIXME: use correct DLL path (also after "make install")
-    c_dyn_linker="$c_dyn_linker -Wl,${abs_top_builddir}/bin/${GAParch}/gap.dll"
-fi
+GAP_CFLAGS="${GAP_CFLAGS} ${GAC_CFLAGS}"
+GAP_CXXFLAGS="${GAP_CXXFLAGS} ${GAC_CFLAGS}"
+GAP_LDFLAGS="${GAP_LDFLAGS} ${GAC_LDFLAGS}"
 
 
 #############################################################################
@@ -118,18 +103,8 @@ cxx_compile () {
 ##
 c_link_dyn () {
     mkdir -p $(dirname $1)
-    echo ${c_dyn_linker} ${GAP_LDFLAGS} -o $1 $2 ${c_addlibs}
-    output_la=${1%.so}.la
-    output_dir=$(dirname $1)
-    ${c_dyn_linker} ${GAP_LDFLAGS} -o "$output_la" $2 ${c_addlibs} || exit 1
-    if [ X"$SYS_IS_CYGWIN32" = X"yes" ] ; then
-        # GAP assumes shared libraries end in .so
-        for dllfile in $(cd $output_dir/.libs; ls *.dll); do
-            cp $output_dir/.libs/$dllfile $output_dir/${dllfile%.dll}.so
-        done
-    else
-        cp $output_dir/.libs/*.so $output_dir
-    fi;
+    echo ${c_dyn_linker} -o $1 $2 ${GAP_LDFLAGS} ${c_addlibs}
+    ${c_dyn_linker} -o $1 $2 ${GAP_LDFLAGS} ${c_addlibs} || exit 1
 }
 
 
@@ -164,12 +139,12 @@ process_c_file () {
     c_file=$2
 
     if [ $comp_howfar != "object" ]; then
-       o_file=${gactmp}/$$_${name}.lo
+       o_file=${gactmp}/$$_${name}.o
        temps_o="${temps_o} ${o_file}"
     elif [ "X$output" != "X" ]; then
        o_file=$output
     else 
-       o_file=${name}.lo
+       o_file=${name}.o
     fi
     c_compile $o_file $c_file
     if [ $comp_howfar = "link" ]; then
@@ -189,12 +164,12 @@ process_cxx_file () {
   cxx_file=$2
 
   if [ $comp_howfar != "object" ]; then
-    o_file=${gactmp}/$$_${name}.lo
+    o_file=${gactmp}/$$_${name}.o
     temps_o="${temps_o} ${o_file}"
   elif [ "X$output" != "X" ]; then
     o_file=$output
   else
-    o_file=${name}.lo
+    o_file=${name}.o
   fi
   cxx_compile $o_file $cxx_file
   if [ $comp_howfar = "link" ]; then
@@ -360,7 +335,7 @@ for input in ${inputs}; do
             name=$(basename ${input} .o)
             process_o_file $name $input;;
 
-        *.lo) # look over '.lo' source files
+        *.lo) # look over '.lo' source files (for backwards compatibility)
             name=$(basename ${input} .lo)
             process_o_file $name $input;;
         esac
@@ -374,7 +349,7 @@ if [ $comp_howfar = "link" ]; then
         exit 1
     fi
 
-    if [ "X${output}" = "X" ]; then output="${name}.la"; fi
+    if [ "X${output}" = "X" ]; then output="${name}.so"; fi
     c_link_dyn ${output} "${objects}"
     
     if [ "$savetemps" = "true" ]; then
diff --git a/configure.ac b/configure.ac
index a24f9cbf785..142a902e127 100644
--- a/configure.ac
+++ b/configure.ac
@@ -993,5 +993,4 @@ AC_CONFIG_FILES([GNUmakefile])
 AC_CONFIG_FILES([CITATION])
 AC_CONFIG_FILES([doc/make_doc], [chmod +x doc/make_doc])
 AC_CONFIG_FILES([doc/versiondata])
-AC_CONFIG_FILES([gac:cnf/gac.in], [chmod +x gac])
 AC_OUTPUT
diff --git a/etc/Makefile.gappkg b/etc/Makefile.gappkg
index 8a8b2ad3a7b..4b0ea9574fe 100644
--- a/etc/Makefile.gappkg
+++ b/etc/Makefile.gappkg
@@ -40,12 +40,6 @@
 # read GAP's build settings
 include $(GAPPATH)/sysinfo.gap
 
-# hack to support GAP <= 4.9
-ifndef GAP_KERNEL_MAJOR_VERSION
-  KEXT_CFLAGS += -I$(GAP_LIB_DIR)/src
-  KEXT_CXXFLAGS += -I$(GAP_LIB_DIR)/src
-endif
-
 # honor used supplied flags
 KEXT_CFLAGS += $(CPPFLAGS)
 KEXT_CFLAGS += $(CFLAGS)
@@ -74,12 +68,12 @@ all: $(KEXT_SO)
 
 ########################################################################
 # Object files
-# For each file FOO.c in SOURCES, add gen/FOO.lo to KEXT_OBJS; similar
+# For each file FOO.c in SOURCES, add gen/FOO.o to KEXT_OBJS; similar
 # for .cc files
 ########################################################################
-KEXT_OBJS = $(patsubst %.s,gen/%.lo, \
-            $(patsubst %.cc,gen/%.lo, \
-            $(patsubst %.c,gen/%.lo, \
+KEXT_OBJS = $(patsubst %.s,gen/%.o, \
+            $(patsubst %.cc,gen/%.o, \
+            $(patsubst %.c,gen/%.o, \
                 $(KEXT_SOURCES))))
 
 ########################################################################
@@ -100,7 +94,7 @@ endif
 ########################################################################
 
 # List of all (potential) dependency files, derived from KEXT_OBJS
-KEXT_DEPFILES = $(patsubst %.lo,%.d,$(KEXT_OBJS))
+KEXT_DEPFILES = $(patsubst %.o,%.d,$(KEXT_OBJS))
 
 # Include the dependency tracking files
 -include $(KEXT_DEPFILES)
@@ -117,19 +111,19 @@ KEXT_DEPFLAGS = -MQ "$@" -MMD -MP -MF $(@D)/$(*F).d
 
 # build rule for C code
 # The dependency on Makefile ensures that re-running configure recompiles everything
-gen/%.lo: %.c Makefile
+gen/%.o: %.c Makefile
 	@mkdir -p $(@D)
 	$(QUIET_GAC)$(GAC) -d -p "$(KEXT_DEPFLAGS)" -p "$(KEXT_CFLAGS)" -c $< -o $@
 
 # build rule for C++ code
 # The dependency on Makefile ensures that re-running configure recompiles everything
-gen/%.lo: %.cc Makefile
+gen/%.o: %.cc Makefile
 	@mkdir -p $(@D)
 	$(QUIET_GAC)$(GAC) -d -p "$(KEXT_DEPFLAGS)" -p "$(KEXT_CXXFLAGS)" -c $< -o $@
 
 # build rule for assembler code
 # The dependency on Makefile ensures that re-running configure recompiles everything
-gen/%.lo: %.s Makefile
+gen/%.o: %.s Makefile
 	@mkdir -p $(@D)
 	$(QUIET_GAC)$(GAC) -d -p "$(KEXT_DEPFLAGS)" -p "$(KEXT_CFLAGS)" -c $< -o $@