[Bug c/100576] New: ICE at -O1 and above: in decompose, at wide-int.h:984

[Bug c/100576] New: ICE at -O1 and above: in decompose, at wide-int.h:984

[cnsun at uwaterloo dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

            Bug ID: 100576
           Summary: ICE at -O1 and above: in decompose, at wide-int.h:984
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: cnsun at uwaterloo dot ca
  Target Milestone: ---

$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/scratch/software/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/12.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/configure
--enable-languages=c,c++,lto --enable-checking-yes --enable-multiarch
--prefix=/scratch/software/gcc-trunk --disable-bootstrap
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 12.0.0 20210511 (experimental) [master revision
:61d4686bb:71d38ec80008afdbb9a059253407d80598b765c0] (GCC)

$ cat mutant.c
const char si16_4_rep[] = {0x12};
eq_si16_x() {
  int n, b = sizeof si16_4_rep;
  const *p, *q = si16_4_rep;
  n += memcmp(p, q, b);
  if (n)
    __builtin_abort();
}

$ gcc-trunk -O1 mutant.c
mutant.c:2:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
    2 | eq_si16_x() {
      | ^~~~~~~~~
mutant.c: In function ‘eq_si16_x’:
mutant.c:4:10: warning: type defaults to ‘int’ in declaration of ‘p’
[-Wimplicit-int]
    4 |   const *p, *q = si16_4_rep;
      |          ^
mutant.c:4:14: warning: type defaults to ‘int’ in declaration of ‘q’
[-Wimplicit-int]
    4 |   const *p, *q = si16_4_rep;
      |              ^
mutant.c:4:18: warning: initialization of ‘const int *’ from incompatible
pointer type ‘const char *’ [-Wincompatible-pointer-types]
    4 |   const *p, *q = si16_4_rep;
      |                  ^~~~~~~~~~
mutant.c:5:8: warning: implicit declaration of function ‘memcmp’
[-Wimplicit-function-declaration]
    5 |   n += memcmp(p, q, b);
      |        ^~~~~~
mutant.c:1:1: note: include ‘<string.h>’ or provide a declaration of ‘memcmp’
  +++ |+#include <string.h>
    1 | const char si16_4_rep[] = {0x12};
mutant.c:5:21: warning: ‘memcmp’ argument 3 type is ‘int’ where ‘long unsigned
int’ is expected in a call to built-in function declared without prototype
[-Wbuiltin-declaration-mismatch]
    5 |   n += memcmp(p, q, b);
      |                     ^
<built-in>: note: built-in ‘memcmp’ declared here
during RTL pass: expand
mutant.c:5:8: internal compiler error: in decompose, at wide-int.h:984
    5 |   n += memcmp(p, q, b);
      |        ^~~~~~~~~~~~~~~
0x679a02 wi::int_traits<generic_wide_int<wide_int_ref_storage<false, false> >
>::decompose(long*, unsigned int, generic_wide_int<wide_int_ref_storage<false,
false> > const&)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/wide-int.h:984
0x67e3d1 wi::int_traits<generic_wide_int<wide_int_storage> >::decompose(long*,
unsigned int, generic_wide_int<wide_int_storage> const&)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/tree.h:3479
0x67e3d1 wide_int_ref_storage<true,
false>::wide_int_ref_storage<generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_storage> const&, unsigned int)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/wide-int.h:1034
0x67e3d1 generic_wide_int<wide_int_ref_storage<true, false>
>::generic_wide_int<generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_storage> const&, unsigned int)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/wide-int.h:790
0x67e3d1 bool wi::ltu_p<generic_wide_int<wide_int_ref_storage<false, false> >,
generic_wide_int<wide_int_storage>
>(generic_wide_int<wide_int_ref_storage<false, false> > const&,
generic_wide_int<wide_int_storage> const&)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/wide-int.h:1937
0x67e3d1 bool wi::leu_p<generic_wide_int<wide_int_storage>,
generic_wide_int<wide_int_ref_storage<false, false> >
>(generic_wide_int<wide_int_storage> const&,
generic_wide_int<wide_int_ref_storage<false, false> > const&)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/wide-int.h:1979
0x67e3d1 check_nul_terminated_array(tree_node*, tree_node*, tree_node*)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:1228
0xa0ad9e check_access(tree_node*, tree_node*, tree_node*, tree_node*,
tree_node*, access_mode, access_data const*)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:4669
0xa0d0e7 check_read_access
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:4909
0xa0e1a1 check_read_access
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:4904
0xa0e1a1 expand_builtin_memcmp
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:7049
0xa12154 expand_builtin(tree_node*, rtx_def*, rtx_def*, machine_mode, int)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/builtins.c:10226
0xb6243c expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/expr.c:11405
0xb6cf58 store_expr(tree_node*, rtx_def*, int, bool, bool)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/expr.c:5986
0xb6e59f expand_assignment(tree_node*, tree_node*, bool)
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/expr.c:5721
0xa3cb0b expand_call_stmt
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/cfgexpand.c:2841
0xa3cb0b expand_gimple_stmt_1
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/cfgexpand.c:3847
0xa3cb0b expand_gimple_stmt
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/cfgexpand.c:4011
0xa42809 expand_gimple_basic_block
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/cfgexpand.c:6048
0xa4445f execute
        /tmp/tmp.BriefQJ2R3-gcc-builder/gcc/gcc/cfgexpand.c:6732
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

[Bug c/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-05-13
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
                 CC|                            |marxin at gcc dot gnu.org,
                   |                            |msebor at gcc dot gnu.org
            Summary|ICE at -O1 and above: in    |[11/12 Regression] ICE at
                   |decompose, at               |-O1 and above: in
                   |wide-int.h:984              |decompose, at
                   |                            |wide-int.h:984 since
                   |                            |r11-2928-gd14c547abd484d35

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Started with r11-2928-gd14c547abd484d35.

[Bug c/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|tree-ssa                    |12.0
   Target Milestone|---                         |11.2
           Keywords|                            |ice-on-valid-code

[Bug middle-end/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
           Keywords|                            |diagnostic

[Bug middle-end/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Slightly cleaned up testcase (but needs the unprototyped memcmp):
const char v[] = {0x12};

void
foo (int n, const char *p)
{
  int b = sizeof v;
  n += memcmp (p, v, b);
  if (n)
    __builtin_abort();
}

[Bug middle-end/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 50827
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50827&action=edit
gcc12-pr100576.patch

Untested fix.

[Bug middle-end/100576] [11/12 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:e6683450f4a26dae7774be735a3429f48aee9565

commit r12-906-ge6683450f4a26dae7774be735a3429f48aee9565
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed May 19 12:05:30 2021 +0200

    builtins: Fix ICE with unprototyped builtin call [PR100576]

    For unprototyped builtins the checking we perform is only about whether
    the used argument is integral, pointer etc., not the exact precision.
    We emit a warning about the problem though:
    pr100576.c: In function âfooâ:
    pr100576.c:9:11: warning: implicit declaration of function âmemcmpâ
[-Wimplicit-function-declaration]
        9 |   int n = memcmp (p, v, b);
          |           ^~~~~~
    pr100576.c:1:1: note: include â<string.h>â or provide a declaration of
âmemcmpâ
      +++ |+#include <string.h>
        1 | /* PR middle-end/100576 */
    pr100576.c:9:25: warning: âmemcmpâ argument 3 type is âintâ where
âlong unsigned intâ is expected in a call to built-in function declared
without prototype
    +[-Wbuiltin-declaration-mismatch]
        9 |   int n = memcmp (p, v, b);
          |                         ^
    It means in the testcase below where the user incorrectly called memcmp
    with last argument int rather then size_t, the warning stuff in builtins.c
    ICEs because it compares a wide_int from such a bound with another wide_int
    which has precision of size_t/sizetype and wide_int asserts the compared
    wide_ints are compatible.

    Fixed by forcing the bound to have the right type.

    2021-05-19  Jakub Jelinek  <jakub@redhat.com>

            PR middle-end/100576
            * builtins.c (check_read_access): Convert bound to size_type_node
if
            non-NULL.

            * gcc.c-torture/compile/pr100576.c: New test.

[Bug middle-end/100576] [11 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[11/12 Regression] ICE at   |[11 Regression] ICE at -O1
                   |-O1 and above: in           |and above: in decompose, at
                   |decompose, at               |wide-int.h:984 since
                   |wide-int.h:984 since        |r11-2928-gd14c547abd484d35
                   |r11-2928-gd14c547abd484d35  |

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed on the trunk so far.

[Bug middle-end/100576] [11 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:f4d6ea0c64bbbbe45add18294bfbd2ceb6512bbd

commit r11-8489-gf4d6ea0c64bbbbe45add18294bfbd2ceb6512bbd
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed May 19 12:05:30 2021 +0200

    builtins: Fix ICE with unprototyped builtin call [PR100576]

    For unprototyped builtins the checking we perform is only about whether
    the used argument is integral, pointer etc., not the exact precision.
    We emit a warning about the problem though:
    pr100576.c: In function âfooâ:
    pr100576.c:9:11: warning: implicit declaration of function âmemcmpâ
[-Wimplicit-function-declaration]
        9 |   int n = memcmp (p, v, b);
          |           ^~~~~~
    pr100576.c:1:1: note: include â<string.h>â or provide a declaration of
âmemcmpâ
      +++ |+#include <string.h>
        1 | /* PR middle-end/100576 */
    pr100576.c:9:25: warning: âmemcmpâ argument 3 type is âintâ where
âlong unsigned intâ is expected in a call to built-in function declared
without prototype
    +[-Wbuiltin-declaration-mismatch]
        9 |   int n = memcmp (p, v, b);
          |                         ^
    It means in the testcase below where the user incorrectly called memcmp
    with last argument int rather then size_t, the warning stuff in builtins.c
    ICEs because it compares a wide_int from such a bound with another wide_int
    which has precision of size_t/sizetype and wide_int asserts the compared
    wide_ints are compatible.

    Fixed by forcing the bound to have the right type.

    2021-05-19  Jakub Jelinek  <jakub@redhat.com>

            PR middle-end/100576
            * builtins.c (check_read_access): Convert bound to size_type_node
if
            non-NULL.

            * gcc.c-torture/compile/pr100576.c: New test.

    (cherry picked from commit e6683450f4a26dae7774be735a3429f48aee9565)

[Bug middle-end/100576] [11 Regression] ICE at -O1 and above: in decompose, at wide-int.h:984 since r11-2928-gd14c547abd484d35

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100576

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

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

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed.