https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96190
Bug ID: 96190
Summary: --enable-default-pie on sparc uses crtbeginS.o
(correct) and crtend.o (incorrect)
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: driver
Assignee: unassigned at gcc dot gnu.org
Reporter: slyfox at inbox dot ru
Target Milestone: ---
The side-effect of the crtbeginS.o/crtend.o mismatch are:
- R_SPARC_NONE relocations in final executables: https://sourceware.org/PR26236
- TEXTRELs in binaries
Simple reproducer:
$ echo 'int main(){}' | sparc-unknown-linux-gnu-gcc -x c - -o a
/usr/libexec/gcc/sparc-unknown-linux-gnu/ld: warning: creating a DT_TEXTREL in
object
$ echo 'int main(){}' | sparc-unknown-linux-gnu-gcc -x c - -o a -no-pie
$ echo 'int main(){}' | sparc-unknown-linux-gnu-gcc -x c - -o a -pie
gcc is built as:
"""
Using built-in specs.
COLLECT_GCC=/usr/bin/sparc-unknown-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/sparc-unknown-linux-gnu/10.1.0/lto-wrapper
Target: sparc-unknown-linux-gnu
Configured with:
/tmp/portage-tmpdir/portage/cross-sparc-unknown-linux-gnu/gcc-10.1.0-r2/work/gcc-10.1.0/configure
--host=x86_64-pc-linux-gnu --target=sparc-unknown-linux-gnu
--build=x86_64-pc-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-pc-linux-gnu/sparc-unknown-linux-gnu/gcc-bin/10.1.0
--includedir=/usr/lib/gcc/sparc-unknown-linux-gnu/10.1.0/include
--datadir=/usr/share/gcc-data/sparc-unknown-linux-gnu/10.1.0
--mandir=/usr/share/gcc-data/sparc-unknown-linux-gnu/10.1.0/man
--infodir=/usr/share/gcc-data/sparc-unknown-linux-gnu/10.1.0/info
--with-gxx-include-dir=/usr/lib/gcc/sparc-unknown-linux-gnu/10.1.0/include/g++-v10
--with-python-dir=/share/gcc-data/sparc-unknown-linux-gnu/10.1.0/python
--enable-languages=c,c++,fortran --enable-obsolete --enable-secureplt
--disable-werror --with-system-zlib --enable-nls --without-included-gettext
--enable-checking=release --with-bugurl=https://bugs.gentoo.org/
--with-pkgversion='Gentoo 10.1.0-r2 p3' --disable-esp --enable-libstdcxx-time
--enable-poison-system-directories --with-sysroot=/usr/sparc-unknown-linux-gnu
--disable-bootstrap --enable-__cxa_atexit --enable-clocale=gnu
--disable-multilib --disable-fixed-point --enable-targets=all --enable-libgomp
--disable-libmudflap --disable-libssp --disable-libada --disable-systemtap
--enable-vtable-verify --without-zstd --enable-lto --without-isl
--enable-default-pie --enable-default-ssp
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 10.1.0 (Gentoo 10.1.0-r2 p3)
"""
I think the bug here is in SPEC files where crtendS.o is only pulled by
explicit options:
gcc/config/sparc/linux.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s\
gcc/config/sparc/linux64.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s\
AFAIu it should be something similar to generic case:
gcc/config/gnu-user.h: shared|static-pie|" PIE_SPEC ":crtendS.o%s; \
Does it sound about right? Should other targets follow as well? Specifically:
gcc/config/alpha/linux.h: crti.o%s
%{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/alpha/linux.h: crti.o%s
%{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/alpha/linux.h: %{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s"
gcc/config/bfin/linux.h: crti.o%s %{shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/c6x/uclinux-elf.h: "%{!shared:crt1%O%s} crti%O%s
%{shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/csky/csky-linux-elf.h: crti.o%s
%{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/csky/csky-linux-elf.h: "%{shared|pie:crtendS.o%s;:crtend.o%s}
crtn.o%s"
gcc/config/frv/linux.h: crti.o%s
%{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/frv/linux.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s"
gcc/config/ia64/linux.h: crti.o%s %{shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/ia64/linux.h: crti.o%s %{shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/ia64/linux.h: %{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s"
gcc/config/m32r/linux.h: crti.o%s
%{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}"
gcc/config/m32r/linux.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s"
gcc/config/sparc/linux.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s\
gcc/config/sparc/linux64.h: "%{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s\
