On 02/15/2012 06:09 PM, Rainer Orth wrote:
> Paolo Bonzini <bonz...@gnu.org> writes:
>
>> This must be a separate macro in acinclude.m4 that is AC_REQUIREd from
>> gcc_AC_INITFINI_ARRAY.
>
> Here's an updated patch that does so. During testing, I found one
> additional complication, though. With the Sun as/GNU ld combination on
> Solaris 11/x86, after the bootstrap had completed, all programs linked
> against libgcc_s.so.1 SEGVed with a stacktrace like this:
>
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 1 (LWP 1)]
> 0x00002000 in ?? ()
> (gdb) where
> #0 0x00002000 in ?? ()
> #1 0xfefcd73f in call_array () from /usr/lib/ld.so.1
> #2 0xfefcd8bd in call_init () from /usr/lib/ld.so.1
> #3 0xfefcc8e1 in setup () from /usr/lib/ld.so.1
> #4 0xfefdcfd8 in _setup () from /usr/lib/ld.so.1
> #5 0xfefc0674 in _rt_boot () from /usr/lib/ld.so.1
> #6 0x0804796c in ?? ()
> #7 0x08047ab0 in ?? ()
> Backtrace stopped: previous frame inner to this frame (corrupt stack?)
>
> The problem turned out to be that with
>
> .section .init_array
>
> as generates
>
> Section Header[5]: sh_name: .init_array
> sh_addr: 0 sh_flags: 0
> sh_size: 0x4 sh_type: [ SHT_PROGBITS ]
> sh_offset: 0x344 sh_entsize: 0
> sh_link: 0 sh_info: 0
> sh_addralign: 0x4
>
> i.e. empty sh_flags. gld seems to mishandle this, since the
> corresponding .initarray entry is bad, as can be seen with runtime
> linker debugging:
>
> $ LD_DEBUG=init LD_PRELOAD=./libgcc_s.so.1 ls
> [...]
> 02032: 1: calling .initarray[0]:0xfed77100: ./libgcc_s.so.1
> 02032: 1: calling .initarray[1]:0x2000: ./libgcc_s.so.1
> Segmentation Fault
>
> If I change the above to
>
> .section .init_array,"aw",@progbits
>
> everything works fine with as/gld, but breaks again with gas/gld since
> gas warns about @progbits here. It turned out that
>
> .section .init_array,"aw"
>
> is fine with both assemblers, while as doesn't understand @init_array.
> That's what the patch below uses.
>
>> Can you test Linux too? The change of -e0 looks good, but I'd rather check
>> on the actual system.
>
> This patch has been bootstrapped on i386-pc-solaris2.{8, 9, 10, 11} with
> as/ld, gas/ld and gas/gld, i386-pc-solaris2.11 with as/gld, as well as
> x86_64-unknown-linux-gnu, correctly detecting .init_array etc. support
> on the gld configurations. It was also included with
> sparc-sun-solaris2.* bootstraps, but even with gas/gld the configure
> test fails. I've got to investigate that separately.
>
> Ok for mainline now?
>
> Thanks.
> Rainer
>
>
> 2012-01-20 Rainer Orth <r...@cebitec.uni-bielefeld.de>
>
> PR target/50166
> * acinclude.m4 (gcc_AC_INITFINI_ARRAY): Require gcc_SUN_LD_VERSION.
> Define _start.
> Remove -e 0 from $gcc_cv_ld invocation.
> Only use __GLIBC_PREREQ if defined.
> Enable on Solaris since Solaris 8 patch.
> (gcc_SUN_LD_VERSION): New macro.
> * configure.ac (ld_ver) <*-*-solaris2*>: Refer to
> gcc_SUN_LD_VERSION for version number format.
> * configure: Regenerate.
> * varasm.c (get_elf_initfini_array_priority_section): Use
> get_section instead of get_unnamed_section to emit
> .init_array/.fini_array with default priority.
Build parts are okay. I cannot approve the varasm.c changes.
Paolo
