On Thu, Oct 17, 2024 at 7:52 PM ChenQi <qi.c...@windriver.com> wrote:
>
> Hi Fortran community,
>
> I recently got a buildpath issue when building libgfortran. I'm sending
> out email to this mailing list first, but if you think it's a bug
> instead of some expected behavior, please let me know and I'll file a bug.
>
> Here's the issue: the generated binary has buildpath in the
> DW_AT_producer section. Below are some output from 'readelf --debug-dump
> libgfortran.so.5.0.0'.
>
> """
>
> <0><1a37d3>: Abbrev Number: 4 (DW_TAG_compile_unit)
> <1a37d4> DW_AT_producer : (indirect string, offset:
> 0xd653): GNU Fortran2008 14.2.0 -m64 -march=core2 -mtune=core2 -msse3
> -mfpmath=sse -mshstk -g -O2 -O2 -fstack-protector-strong -fimplicit-none
> -fno-repack-arrays -fno-underscoring -fcf-protection=full
> -fallow-leading-underscore -fbuilding-libgfortran -fPIC
> -fintrinsic-modules-path
> /ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/recipe-sysroot-native/usr/bin/x86_64-poky-linux/../../lib/x86_64-poky-linux/gcc/x86_64-poky-linux/14.2.0/finclude
> -fpre-include=../../../../recipe-sysroot/usr/include/finclude/math-vector-fortran.h
>
> """
>
> The problem is that this '-fintrinsic-modules-path' is not passed by me.
> Use some .o file as an example. Here's command to build out
> .libs/_mod_r17.o:
>
> """
>
> libtool: compile: x86_64-poky-linux-gfortran -m64 -march=core2
> -mtune=core2 -msse3 -mfpmath=sse -fstack-protector-strong -O2
> -D_FORTIFY_SOURCE=2 -Wformat -Wformat-security -Werror=format-security
> --sysroot=../../../../recipe-sysroot -fcanon-prefix-map
> -fdebug-prefix-map=/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work-shared/gcc-14.2.0-r0/gcc-14.2.0=/usr/src/debug/libgfortran/14.2.0
> -fdebug-prefix-map=/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/gcc-14.2.0/build.x86_64-poky-linux.x86_64-poky-linux=/usr/src/debug/libgfortran/14.2.0
> -fdebug-prefix-map=/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/recipe-sysroot-native=
> -DHAVE_CONFIG_H -I. -I../../../../../../../../work-shared/gcc-14.2.\
> 0-r0/gcc-14.2.0/libgfortran
> -iquote../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/io
> -I../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/../gcc
> -I../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/../gcc/config
> -I/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/gcc-14.2.0/build.x86_64-poky-linux.x86_64-poky-linux/x86_64-poky-linux/libgfortran/../.././gcc
> -I../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/../libgcc
> -I/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/gcc-14.2.0/build.x86_64-poky-linux.x86_64-poky-linux/x86_64-poky-linux/libgfortran/../libgcc
> -I../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/../libbacktrace
> -I/ala-lpggp72/qichen/Yocto/builds/build-poky/tmp/work/core2-64-poky-linux/libgfortran/14.2.0/gcc-14.2.0/build.x86_64-poky-linux.x86_64-poky-linux/x86_64-poky-linux/libgfortran/../libbacktrace
> -I../libbacktrace -I . -Wall -Werror -fimplicit-none -fno-repack-arrays
> -fno-underscoring -fcf-protection -mshstk -fallow-leading-underscore
> -fbuilding-libgfortran -g -O2 -c
> ../../../../../../../../work-shared/gcc-14.2.0-r0/gcc-14.2.0/libgfortran/generated/_mod_r17.F90
> -fPIC -o .libs/_mod_r17.o
>
> """
>
> You can see that there's no '-fintrinsic-modules-path' there. This means
> that this '-fintrinsic-modules-path' is added automatically by gfortran.
> And the generated _mod_r17.o has buildpath encoded.
>
> I tried to add '-fintrinsic-modules-path=/not/exist', hoping that no
> extra '-fintrinsic-modules-path' option would be added, but it does not
> work.
>
> I searched the whole gcc source codes, and really cannot find any codes
> that adds this option automatically.
It comes from the fortran specs:
```
#define F951_OPTIONS "%(cc1_options) %{J*} \
%{!nostdinc:-fintrinsic-modules-path finclude%s}" \
TARGET_F951_OPTIONS \
"%{!fsyntax-only:%(invoke_as)}"
...
{"@f95",
"f951 %i %{E:%{!cpp:%egfortran does not support -E without -cpp}}\
%{cpp:" F951_CPP_OPTIONS ";: " CPP_FORWARD_OPTIONS "} \
%{!E:" F951_OPTIONS "}", 0, 0, 0},
```
I see the producer string should only have the saved options if
dwarf_record_gcc_switches is true which is the default.
You can turn that off with -gno-record-gcc-switches so build
directories don't show up.
Thanks,
Andrew Pinski
>
> Does someone know what's going on? Why is this
> '-fintrinsic-modules-path' added automatically? Is there any way to get
> rid of this buildpath?
>
> Thanks in advance.
>
> Regards,
>
> Qi
>
