diff options
| -rw-r--r-- | sysdeps/powerpc/powerpc64/le/Makefile | 27 | ||||
| -rw-r--r-- | sysdeps/powerpc/powerpc64/le/no_ldbl_gnu_attribute.c | 30 |
2 files changed, 56 insertions, 1 deletions
diff --git a/sysdeps/powerpc/powerpc64/le/Makefile b/sysdeps/powerpc/powerpc64/le/Makefile index 96834d3e2b..6afa1228dd 100644 --- a/sysdeps/powerpc/powerpc64/le/Makefile +++ b/sysdeps/powerpc/powerpc64/le/Makefile @@ -10,7 +10,32 @@ ifeq ($(ibm128-fcts),yes) ibm128-abi-CFLAGS := -mabi=ibmlongdouble type-ldouble-CFLAGS += $(ibm128-abi-CFLAGS) no-gnu-attribute-CFLAGS = -mno-gnu-attribute -endif + +# This is a very gnarly workaround to static libgcc providing a .gnu.attribute +# in ibm128 functions. This is not a bug in static libgcc as normal users +# should only ever link ibm128 or ieee128 routines, never both. We are the +# exception which allows the decision to be deferred to user libraries or +# applications. +# +# We built an object file and extract the desired .gnu.attributes section +# to be inserted into lib{c,m}.so. +ifeq ($(build-shared),yes) +before-compile += $(common-objpfx)no_ldbl_gnu_attribute.bin + +$(common-objpfx)no_ldbl_gnu_attribute.bin: $(..)sysdeps/powerpc/powerpc64/le/no_ldbl_gnu_attribute.c + $(filter-out $(no-gnu-attribute-CFLAGS),$(compile.c)) -o $(basename $@).o + $(OBJCOPY) --dump-section=.gnu.attributes=$@.tmp $(basename $@).o + mv $@.tmp $@ + +define after-link +if [ ! -z "$(filter libm.so libc.so,$(notdir $1))" ]; then \ + echo "Replacing .gnu.attributes in $1"; \ + $(OBJCOPY) --update-section=.gnu.attributes=$(common-objpfx)no_ldbl_gnu_attribute.bin $1; \ +fi +endef + +endif # ifeq ($(build-shared),yes) +endif # ifeq ($(ibm128-fcts),yes) # All _Float128 files should be built assuming an ibm128 long double. # Likewise, this avoids some old GCC 7 compiler bugs whereby calls diff --git a/sysdeps/powerpc/powerpc64/le/no_ldbl_gnu_attribute.c b/sysdeps/powerpc/powerpc64/le/no_ldbl_gnu_attribute.c new file mode 100644 index 0000000000..8ffee30560 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/le/no_ldbl_gnu_attribute.c @@ -0,0 +1,30 @@ +/* File to generate desired .gnu.attribute section + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library. If not, see + <https://www.gnu.org/licenses/>. */ + +/* This generates a .gnu.attributes sections with + the default toolchain settings and an indeterminate + long double format. */ +long double _not_used; + +/* Some older GCC versions need a little more convincing to + generate .gnu.attributes. */ +double +foo (double d) +{ + return d; +} |