GCC 11.1.10 ld: warning: .init_array section has zero size

[Chris Packham]

On 18/06/21 3:37 pm, Alan Modra wrote:
> On Fri, Jun 18, 2021 at 12:49:55AM +0000, Chris Packham wrote:
>> On 18/06/21 12:30 pm, Alan Modra wrote:
>>> On Thu, Jun 17, 2021 at 09:20:56PM +0000, Chris Packham via Binutils wrote:
>>>>>> warning: .init_array section has zero size
>>>> I'm in the process of getting a GCC bugzilla account so I was also going
>>>> to report there.
>>> Before doing that, inspect all of the object files you are linking
>>> with readelf -SW.  (Use gcc -v to see the linker command line, and all
>>> of the objects/libraries involved, or link with -Wl,-t to have the
>>> linker report files it links.)  One or more of them will have a zero
>>> size .init_array section.  If they were objects created by gcc from
>>> source or supplied with the compiler (crtbegin*.o, crtend*.o) then a
>>> gcc bug report is appropriate.  If they are other startup files, libc
>>> objects or assembly source objects you probably shouldn't complain
>>> about gcc.
>>>
>> Looks like crtbegin.o has a zero-sized .init_array/.fini_array
> OK..  I built mainline gcc and the gcc-11 branch from source just now,
> a cross from x86_64-linux to arm-linuxeabi, and those sections have
> size 4 in my crtbegin.o files.  For gcc-11 the entry in .init_array
> comes from crtstuff.c line 504.
>
> That datapoint might mean the problem is caused by some patch you have
> applied, or it might just be some configuration difference.

I've tried dropping all the patches crosstool-ng has for GCC 11.1.0 
(most are just for compiling on macOS). Same result.

> I configure gcc using
> --with-sysroot=/home/gnu/arm-linuxeabi --prefix=/usr/local \
>    --target=arm-linuxeabi --disable-nls --enable-__cxa_atexit \
>    --disable-libsanitizer --enable-decimal-float=no \
>    --disable-bootstrap --enable-languages=c,c++
>
Right now crosstool-ng still uses a 3 pass build so the first two passes 
use --enable-languages=c

I do note the following

x-tool@063c4281c760:~$ find ./.build/arm-unknown-linux-gnueabi/build/ 
-name config.log | xargs grep -n initfini_array
./.build/arm-unknown-linux-gnueabi/build/build-cc-gcc-final/gcc/config.log:7854:gcc_cv_initfini_array=no
./.build/arm-unknown-linux-gnueabi/build/build-binutils-host-x86_64-build_pc-linux-gnu/ld/config.log:3225:enable_initfini_array='yes'
./.build/arm-unknown-linux-gnueabi/build/build-cc-gcc-core-pass-2/gcc/config.log:7854:gcc_cv_initfini_array=no
./.build/arm-unknown-linux-gnueabi/build/build-cc-gcc-core-pass-1/gcc/config.log:7848:gcc_cv_initfini_array=no

crosstool-ng doesn't pass either --enable-initfini-array or 
--disable-initfini-array relying on the configure guessing.