[Bug sanitizer/63845] New: c-c++-common/asan/bitfield-1.c fails on i?86 -with -fpic

[Bug sanitizer/63845] New: c-c++-common/asan/bitfield-1.c fails on i?86 -with -fpic

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

            Bug ID: 63845
           Summary: c-c++-common/asan/bitfield-1.c fails on i?86 -with
                    -fpic
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ubizjak at gmail dot com
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org
            Target: i686-pc-linux-gnu

Found when running testsuite on x86_64 -m32 with -fpic:

$ ~/gcc-build/gcc/cc1 -quiet -fsanitize=address -m32 -fpic bitfield-1.c 

bitfield-1.c: In function ‘main’:
bitfield-1.c:23:1: internal compiler error: in df_refs_verify, at
df-scan.c:4088
 }
 ^
0x6e9a6b df_refs_verify
        ../../gcc-svn/trunk/gcc/df-scan.c:4088
0x6ed861 df_insn_refs_verify
        ../../gcc-svn/trunk/gcc/df-scan.c:4161
0x6ede02 df_bb_verify
        ../../gcc-svn/trunk/gcc/df-scan.c:4188
0x6f1457 df_scan_verify()
        ../../gcc-svn/trunk/gcc/df-scan.c:4320
0x6df084 df_verify()
        ../../gcc-svn/trunk/gcc/df-core.c:1860
0x6df084 df_analyze_1
        ../../gcc-svn/trunk/gcc/df-core.c:1248
0x8ddbdb ira
        ../../gcc-svn/trunk/gcc/ira.c:5158
0x8ddbdb execute
        ../../gcc-svn/trunk/gcc/ira.c:5507
Please submit a full bug report,


The failure with -O2 is a bit different:

$ ~/gcc-build/gcc/cc1 -quiet -fsanitize=address -m32 -fpic -O2 bitfield-1.c 
bitfield-1.c: In function ‘main’:
bitfield-1.c:23:1: internal compiler error: Segmentation fault
 }
 ^
0xa4ea8f crash_signal
        ../../gcc-svn/trunk/gcc/toplev.c:358
0x6ea7ff df_install_ref
        ../../gcc-svn/trunk/gcc/df-scan.c:2331
0x6edfa5 df_install_refs
        ../../gcc-svn/trunk/gcc/df-scan.c:2413
0x6ee57b df_refs_add_to_chains
        ../../gcc-svn/trunk/gcc/df-scan.c:2466
0x6f07dc df_bb_refs_record(int, bool)
        ../../gcc-svn/trunk/gcc/df-scan.c:3399
0x6f098c df_scan_blocks()
        ../../gcc-svn/trunk/gcc/df-scan.c:629
0x6ddb52 rest_of_handle_df_initialize
        ../../gcc-svn/trunk/gcc/df-core.c:746
Please submit a full bug report,
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To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-1.c fails on i?86 -with -fpic
Date: Thu, 13 Nov 2014 08:20:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idc845

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-11-13
                 CC|                            |mpolacek at gcc dot gnu.org
      Known to work|                            |4.9.2
   Target Milestone|---                         |5.0
            Summary|c-c++-common/asan/bitfield- |[5 Regression]
                   |1.c fails on i?86 -with     |c-c++-common/asan/bitfield-
                   |-fpic                       |1.c fails on i?86 -with
                   |                            |-fpic
     Ever confirmed|0                           |1
      Known to fail|                            |5.0

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Confirmed.

[Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-[12345].c fails on i?86 -with -fpic

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

Uroš Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[5 Regression]              |[5 Regression]
                   |c-c++-common/asan/bitfield- |c-c++-common/asan/bitfield-
                   |1.c fails on i?86 -with     |[12345].c fails on i?86
                   |-fpic                       |-with -fpic

--- Comment #2 from Uroš Bizjak <ubizjak at gmail dot com> ---
-Os -g fails:

~/gcc-build/gcc/cc1 -quiet -fsanitize=address -m32 -fpic -Os -g bitfield-1.c 
bitfield-1.c: In function ‘main’:
bitfield-1.c:23:1: internal compiler error: in operator[], at vec.h:736
 }
 ^
0x1046c07 vec<df_ref_d*, va_heap, vl_embed>::operator[](unsigned int)
        ../../gcc-svn/trunk/gcc/vec.h:736
0x1046c07 vec<df_ref_d*, va_heap, vl_ptr>::operator[](unsigned int)
        ../../gcc-svn/trunk/gcc/vec.h:1202
0x1046c07 process_uses
        ../../gcc-svn/trunk/gcc/fwprop.c:212
0x10472ad single_def_use_dom_walker::before_dom_children(basic_block_def*)
        ../../gcc-svn/trunk/gcc/fwprop.c:253
0x103e3d7 dom_walker::walk(basic_block_def*)
        ../../gcc-svn/trunk/gcc/domwalk.c:188
0x1046884 build_single_def_use_links
        ../../gcc-svn/trunk/gcc/fwprop.c:310
0x1046884 fwprop_init
        ../../gcc-svn/trunk/gcc/fwprop.c:1415
0x104875a fwprop
        ../../gcc-svn/trunk/gcc/fwprop.c:1460
0x104875a execute
        ../../gcc-svn/trunk/gcc/fwprop.c:1509
Please submit a full bug report,
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Subject: [Bug sanitizer/63846] New: c-c++-common/asan/misalign-[12].c fails on i?86 with -fpic
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63846

            Bug ID: 63846
           Summary: c-c++-common/asan/misalign-[12].c fails on i?86 with
                    -fpic
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ubizjak at gmail dot com
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org

Found when running testsuite on x86_64 -m32 with -fpic:

$ ~/gcc-build/gcc/cc1 -quiet -fsanitize=address -m32 -fpic misalign-1.c 
misalign-1.c: In function ‘main’:
misalign-1.c:36:1: error: insn does not satisfy its constraints:
 }
 ^
(insn 122 3 4 2 (set (reg:SI 0 ax [109])
        (reg:SI 109)) misalign-1.c:27 90 {*movsi_internal}
     (nil))
misalign-1.c:36:1: internal compiler error: in extract_constrain_insn_cached,
at recog.c:2242
0x9efbf8 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc-svn/trunk/gcc/rtl-error.c:110
0x9efc1f _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
        ../../gcc-svn/trunk/gcc/rtl-error.c:121
0x9bf159 extract_constrain_insn_cached(rtx_insn*)
        ../../gcc-svn/trunk/gcc/recog.c:2242
0xd81e57 insn_default_length(rtx_insn*)
        ../../gcc-svn/trunk/gcc/config/i386/i386.md:13082
0x788292 shorten_branches(rtx_insn*)
        ../../gcc-svn/trunk/gcc/final.c:1208
0x78891f rest_of_handle_shorten_branches
        ../../gcc-svn/trunk/gcc/final.c:4567
0x78891f execute
        ../../gcc-svn/trunk/gcc/final.c:4596
Please submit a full bug report,
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Subject: [Bug tree-optimization/61559] FAIL: gcc.dg/builtin-bswap-8.c on i686 with -mmovbe
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ida559

--- Comment #16 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Nov 13 08:45:29 2014
New Revision: 217464

URL: https://gcc.gnu.org/viewcvs?rev!7464&root=gcc&view=rev
Log:
2014-12-13  Richard Biener  <rguenther@suse.de>

    PR middle-end/61559
    * match.pd: Implement bswap patterns for transforms checked by
    gcc.dg/builtin-bswap-8.c.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/match.pd

[Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-[12345].c fails on i?86 -with -fpic

[izamyatin at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

Igor Zamyatin <izamyatin at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |izamyatin at gmail dot com

--- Comment #3 from Igor Zamyatin <izamyatin at gmail dot com> ---
I already posted a patch -
http://gcc.gnu.org/ml/gcc-patches/2014-10/msg03318.html

Will ping it today

[Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-[12345].c fails on i?86 -with -fpic

[ienkovich at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

--- Comment #4 from ienkovich at gcc dot gnu.org ---
Author: ienkovich
Date: Thu Nov 20 08:15:21 2014
New Revision: 217825

URL: https://gcc.gnu.org/viewcvs?rev=217825&root=gcc&view=rev
Log:
gcc/

    PR sanitizer/63845
    * function.c (assign_parms): Move init of pic_offset_table_rtx
    from here to...
    * cfgexpand.c (expand_used_vars): ...here.

gcc/testsuite/

    PR sanitizer/63845
    * gcc.dg/asan/pr63845.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/asan/pr63845.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/function.c
    trunk/gcc/testsuite/ChangeLog

[Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-[12345].c fails on i?86 -with -fpic

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Assuming fixed.

[Bug sanitizer/63845] [5 Regression] c-c++-common/asan/bitfield-[12345].c fails on i?86 -with -fpic

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63845

--- Comment #6 from Uroš Bizjak <ubizjak at gmail dot com> ---
*** Bug 63846 has been marked as a duplicate of this bug. ***
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Subject: [Bug sanitizer/63846] c-c++-common/asan/misalign-[12].c fails on i?86 with -fpic
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63846

Uroš Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #2 from Uroš Bizjak <ubizjak at gmail dot com> ---
Dup.

*** This bug has been marked as a duplicate of bug 63845 ***
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idB108

--- Comment #64 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #63)
> Unfortunately for the testcase this doesn't allow moving the division at all
> and we are lucky that we have range information at all because of the fortran
> frontend casting 'n' to unsigned before dividing by it.

If it helps and the semantic is preserved, there is no reason not to completely
change what tree code the Fortran FE generates for loops.

[I think one reason for the odd way tree code for loops is generated is: The
current code makes it simple to permit loops which are always run once, as some
Fortran 66 compilers did. For instance, "DO i = 2, 1" would then be executed
once. (Such loops are not permitted in F66 - and some compilers executed them
once others zero times; since F77, such loops are permitted and executed zero
times. Unsurprisingly, some old code from the 60s relies on the execute once
feature.)

g77 and some commercial compilers have a compile flag like "-f66", gfortran
hasn't and I don't think it ever will.]