From: Aleksandar Rakic <[email protected]>
This patch introduces a new configure-time option --with-multi-buildlist
to allow fine-grained control over which multilib variants are built.
The option accepts a path to a file containing a list of multilib
directories to be included in the build. Each line in the file should
contain a single multilib directory name, matching those generated by
the compiler's --print-multi-lib output.
This mechanism is target-independent and enables users to reduce build
time and binary size by excluding unnecessary multilib variants. It is
especially useful for embedded targets with constrained environments or
vendor-specific requirements.
The option is propagated to both host and target configuration stages,
and used in config-ml.in and gcc/Makefile.in to filter the multilib
list.
Documentation for this feature is added to gcc/doc/install.texi.
* config-ml.in: Use with_multi_buildlist to build multidirs.
Skip configuration for subdir returned by
--print-multi-directory.
* configure: Regenerate.
* configure.ac: Source target-specific configuration fragment
for GCC. Pass through with_multi_buildlist to host and target.
gcc/
* Makefile.in: Add with_multi_buildlist for multilib
configuration control. Pass an additional argument to
genmultilib indicating whether --with-multi-buildlist is set
(true or false). Use with_multi_buildlist to filter
multilib directories in fixinc_list.
* configure: Regenerate.
* configure.ac: Restrict the installed fixedincludes multilibs.
* configure.tgt: New file.
* doc/install.texi: Add --with-multi-buildlist configure option
for multilib filtering.
* genmultilib: Document the new optional eleventh argument
indicating whether --with-multi-buildlist configure option is
set (true or false). Update argument parsing to include this
flag before enable_multilib. Modify reuse rule validation:
- Keep the original error for reuse of nonexistent multilibs
when --with-multi-buildlist is not used.
- Suppress the error only when the new configure option is
active, allowing reuse rules to reference multilibs that are
intentionally excluded from the build.
Cherry-picked 2b2481cc71284ad9db3dff60bd6cab2be678e87e
from https://github.com/MIPS/gcc
Signed-off-by: Robert Suchanek <[email protected]>
Signed-off-by: Chao-ying Fu <[email protected]>
Signed-off-by: Aleksandar Rakic <[email protected]>
---
config-ml.in | 25 ++++++++++++++++++++++++-
configure | 15 +++++++++++++++
configure.ac | 15 +++++++++++++++
gcc/Makefile.in | 19 ++++++++++++++++++-
gcc/configure | 8 ++++++--
gcc/configure.ac | 3 +++
gcc/configure.tgt | 20 ++++++++++++++++++++
gcc/doc/install.texi | 24 ++++++++++++++++++++++++
gcc/genmultilib | 10 +++++++---
9 files changed, 132 insertions(+), 7 deletions(-)
create mode 100644 gcc/configure.tgt
diff --git a/config-ml.in b/config-ml.in
index 645cac822fd..450bd1c05fd 100644
--- a/config-ml.in
+++ b/config-ml.in
@@ -488,6 +488,23 @@ powerpc*-*-* | rs6000*-*-*)
;;
esac
+# Use a filtered multilib list if requested.
+
+if [ x$with_multi_buildlist != x ]; then
+ old_multidirs="${multidirs}"
+ if [ ! -f $with_multi_buildlist ]; then
+ echo "config-ml.in: Failed to find $with_multi_buildlist"
+ exit 1
+ fi
+ multidirs=""
+ for x in ${old_multidirs}; do
+ found=`grep "^${x}$" $with_multi_buildlist`
+ if [ -n "$found" ]; then
+ multidirs="${multidirs} ${x}"
+ fi
+ done
+fi
+
# Remove extraneous blanks from multidirs.
# Tests like `if [ -n "$multidirs" ]' require it.
multidirs=`echo "$multidirs" | sed -e 's/^[ ][ ]*//' -e 's/[ ][ ]*$//' -e 's/[
][ ]*/ /g'`
@@ -597,7 +614,8 @@ else
fi
if [ -z "${with_multisubdir}" ]; then
- ml_subdir=
+ ml_top_subdir=`${CC-gcc} --print-multi-directory 2>/dev/null`
+ ml_subdir=/$ml_top_subdir
ml_builddotdot=
: # ml_srcdotdot= # already set
else
@@ -676,6 +694,11 @@ if [ -n "${multidirs}" ] && [ -z "${ml_norecursion}" ];
then
for ml_dir in ${multidirs}; do
+ if [ "${ml_dir}" == "${ml_top_subdir}" ]; then
+ echo "Skipping configure in multilib subdir ${ml_dir}"
+ continue
+ fi
+
if [ "${ml_verbose}" = --verbose ]; then
echo "Running configure in multilib subdir ${ml_dir}"
echo "pwd: `${PWDCMD-pwd}`"
diff --git a/configure b/configure
index a2e86731b08..738fe645722 100755
--- a/configure
+++ b/configure
@@ -11338,6 +11338,21 @@ if test x${enable_multilib} = x ; then
target_configargs="--enable-multilib ${target_configargs}"
fi
+# Source target-specific configuration fragment for GCC
+if test -d ${srcdir}/gcc; then
+ . ${srcdir}/gcc/configure.tgt
+fi
+
+# Pass through with_multi_buildlist to host and target. 'gcc' needs it for the
+# fixed includes which are multilib'd and target libraries need it as they use
+# config-ml.in.
+if test x${with_multi_buildlist} != x ; then
+ target_configargs="--with-multi-buildlist=${with_multi_buildlist} \
+ ${target_configargs}"
+ host_configargs="--with-multi-buildlist=${with_multi_buildlist} \
+ ${host_configargs}"
+fi
+
# Pass --with-newlib if appropriate. Note that target_configdirs has
# changed from the earlier setting of with_newlib.
if test x${with_newlib} != xno && echo " ${target_configdirs} " | grep "
newlib " > /dev/null 2>&1 && test -d ${srcdir}/newlib ; then
diff --git a/configure.ac b/configure.ac
index 25419a1d2ab..1112598d1b9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3577,6 +3577,21 @@ if test x${enable_multilib} = x ; then
target_configargs="--enable-multilib ${target_configargs}"
fi
+# Source target-specific configuration fragment for GCC
+if test -d ${srcdir}/gcc; then
+ . ${srcdir}/gcc/configure.tgt
+fi
+
+# Pass through with_multi_buildlist to host and target. 'gcc' needs it for the
+# fixed includes which are multilib'd and target libraries need it as they use
+# config-ml.in.
+if test x${with_multi_buildlist} != x ; then
+ target_configargs="--with-multi-buildlist=${with_multi_buildlist} \
+ ${target_configargs}"
+ host_configargs="--with-multi-buildlist=${with_multi_buildlist} \
+ ${host_configargs}"
+fi
+
# Pass --with-newlib if appropriate. Note that target_configdirs has
# changed from the earlier setting of with_newlib.
if test x${with_newlib} != xno && echo " ${target_configdirs} " | grep "
newlib " > /dev/null 2>&1 && test -d ${srcdir}/newlib ; then
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index e8b2a38c8b3..e0e9c632304 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -642,6 +642,9 @@ else
endif
endif
+# Multilib control
+with_multi_buildlist = @with_multi_buildlist@
+
# ------------------------
# Installation directories
# ------------------------
@@ -2328,11 +2331,12 @@ s-mlib: $(srcdir)/genmultilib Makefile
"$(MULTILIB_REQUIRED)" \
"$(if $(MULTILIB_OSDIRNAMES),,$(MULTIARCH_DIRNAME))" \
"$(MULTILIB_REUSE)" \
+ "$(if $(with_multi_buildlist),true,false)" \
"@enable_multilib@" \
> tmp-mlib.h; \
else \
$(SHELL) $(srcdir)/genmultilib '' '' '' '' '' '' '' '' \
- "$(MULTIARCH_DIRNAME)" '' no \
+ "$(MULTIARCH_DIRNAME)" '' '' no \
> tmp-mlib.h; \
fi
$(SHELL) $(srcdir)/../move-if-change tmp-mlib.h multilib.h
@@ -3383,10 +3387,23 @@ fixinc_list: s-fixinc_list; @true
s-fixinc_list : $(GCC_PASSES)
# Build up a list of multilib directories and corresponding sysroot
# suffixes, in form sysroot;multilib.
+# Use a filtered multilib list if requested.
if $(GCC_FOR_TARGET) -print-sysroot-headers-suffix > /dev/null 2>&1;
then \
set -e; for ml in `$(GCC_FOR_TARGET) -print-multi-lib`; do \
multi_dir=`echo $${ml} | sed -e 's/;.*$$//'`; \
flags=`echo $${ml} | sed -e 's/^[^;]*;//' -e 's/@/ -/g'`; \
+ if [ x$(with_multi_buildlist) != x ]; then \
+ if [ ! -f $(with_multi_buildlist) ]; then \
+ echo "fixinc_list: Failed to find $(with_multi_buildlist)"; \
+ exit 1; \
+ fi; \
+ set +e; \
+ found=`grep "^$${multi_dir}$$" $(with_multi_buildlist)`; \
+ set -e; \
+ if [ -z "$$found" ]; then \
+ continue; \
+ fi; \
+ fi; \
sfx=`$(GCC_FOR_TARGET) $${flags} -print-sysroot-headers-suffix`; \
if [ "$${multi_dir}" = "." ]; \
then multi_dir=""; \
diff --git a/gcc/configure b/gcc/configure
index 150ab616414..1341e1cbd3f 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -853,6 +853,7 @@ enable_fixed_point
enable_decimal_float
DEFAULT_INSNEMIT_PARTITIONS
DEFAULT_MATCHPD_PARTITIONS
+with_multi_buildlist
with_float
with_cpu
enable_multiarch
@@ -7870,6 +7871,9 @@ $as_echo "$enable_multiarch$ma_msg_suffix" >&6; }
+# needed for restricting the fixedincludes multilibs that we install
+
+
# default stack clash protection guard size as power of twos in bytes.
# Please keep these in sync with params.def.
stk_clash_min=12
@@ -21454,7 +21458,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 21457 "configure"
+#line 21461 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -21560,7 +21564,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 21563 "configure"
+#line 21567 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
diff --git a/gcc/configure.ac b/gcc/configure.ac
index bdb22d53e2c..ee98191411e 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -877,6 +877,9 @@ AC_MSG_RESULT($enable_multiarch$ma_msg_suffix)
AC_SUBST(with_cpu)
AC_SUBST(with_float)
+# needed for restricting the fixedincludes multilibs that we install
+AC_SUBST(with_multi_buildlist)
+
# default stack clash protection guard size as power of twos in bytes.
# Please keep these in sync with params.def.
stk_clash_min=12
diff --git a/gcc/configure.tgt b/gcc/configure.tgt
new file mode 100644
index 00000000000..2c570b87ded
--- /dev/null
+++ b/gcc/configure.tgt
@@ -0,0 +1,20 @@
+# -*- shell-script -*-
+# Copyright (C) 2025 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not see <http://www.gnu.org/licenses/>.
+
+# This is the target specific configuration file. This is invoked by the
+# autoconf generated configure script. Putting it in a separate shell file
+# lets us skip running autoconf when modifying target specific information.
+
diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 705440ffd33..25306481860 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -1509,6 +1509,30 @@ medlow code model; rv64ima with lp64 and medany code
model
rv64ima-lp64--;--cmodel=medlow,medany
@end smallexample
+@item --with-multi-buildlist=@var{file}
+Specify a file containing a list of multilib directories to build.
+
+Each line in the file should contain a single multilib directory name,
+as printed by @code{gcc --print-multi-lib}. Only the listed directories
+will be built and installed.
+
+This option is useful for reducing build time and binary size by
+excluding unnecessary multilib variants. It is especially beneficial
+for embedded targets or vendor-specific toolchains.
+
+Example file contents:
+
+@smallexample
+mips-r6-hard/lib
+mips-r6-soft/lib32
+mipsel-r6-hard/lib64
+@end smallexample
+
+This option is target-independent and can be used with any architecture
+that supports multilibs. It is passed to both host and target
+configuration stages and used during fixed includes installation and
+multilib directory generation.
+
@item --with-endian=@var{endians}
Specify what endians to use.
Currently only implemented for sh*-*-*.
diff --git a/gcc/genmultilib b/gcc/genmultilib
index 85b241cd72a..d3cb10c51eb 100644
--- a/gcc/genmultilib
+++ b/gcc/genmultilib
@@ -88,6 +88,9 @@
# The optional tenth argument specifies how to reuse multilib for different
# option sets.
+# The optional eleventh argument specifies whether the
+# --with-multi-buildlist configure option is set (true or false).
+
# The last option should be "yes" if multilibs are enabled. If it is not
# "yes", all GCC multilib dir names will be ".".
@@ -108,7 +111,7 @@
# genmultilib 'm64/m32 mno-app-regs|mcmodel=medany' '64 32 alt'
# 'mcmodel?medany=mcmodel?medmid' 'm32/mno-app-regs*
m32/mcmodel=*'
# '' 'm32/!m64/mno-app-regs m32/!m64/mcmodel=medany'
-# '../lib64 ../lib32 alt' '' '' '' yes
+# '../lib64 ../lib32 alt' '' '' '' '' yes
# This produces:
# ". !m64 !m32 !mno-app-regs !mcmodel=medany;",
# "64:../lib64 m64 !m32 !mno-app-regs !mcmodel=medany;",
@@ -139,7 +142,8 @@ osdirnames=$7
multilib_required=$8
multiarch=$9
multilib_reuse=${10}
-enable_multilib=${11}
+with_multi_buildlist=${11}
+enable_multilib=${12}
echo "static const char *const multilib_raw[] = {"
@@ -500,7 +504,7 @@ for rrule in ${multilib_reuse}; do
echo "The rule ${rrule} contains an option absent from
MULTILIB_OPTIONS." >&2
exit 1
fi
- else
+ elif ! ${with_multi_buildlist}; then
echo "The rule ${rrule} is trying to reuse nonexistent multilib." >&2
exit 1
fi
--
2.34.1
