[Bug c++/95579] New: internal compiler error: in sign_mask, at wide-int.h:855

[Bug c++/95579] New: internal compiler error: in sign_mask, at wide-int.h:855

[nmmm at nmmm dot nu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95579

            Bug ID: 95579
           Summary: internal compiler error: in sign_mask, at
                    wide-int.h:855
           Product: gcc
           Version: 10.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nmmm at nmmm dot nu
  Target Milestone: ---

https://gcc.godbolt.org/z/5Dfous

#include <cstdint>

uint16_t byteswap(uint16_t const a){
        constexpr uint8_t b[] = {
                8 * (2 - 1)
        };

        auto const x =
                (0x00ffULL & a) << b[0] |
                (0xff00ULL & a) >> b[0]
        ;

        return static_cast<uint16_t>(x);
}


------------------

<source>: In function 'uint16_t byteswap(uint16_t)':

<source>:12:25: internal compiler error: in sign_mask, at wide-int.h:855

   12 |   (0xff00ULL & a) >> b[0]

      |                         ^

Please submit a full bug report,

with preprocessed source if appropriate.

See <https://gcc.gnu.org/bugs/> for instructions.

Compiler returned: 1

[Bug c++/95579] internal compiler error: in sign_mask, at wide-int.h:855

[nmmm at nmmm dot nu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95579

--- Comment #1 from Nikolay Mihaylov <nmmm at nmmm dot nu> ---
Code compiles on 9.x

[Bug c++/95579] [10/11 Regression] internal compiler error: in sign_mask, at wide-int.h:855

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95579

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Target Milestone|---                         |10.2
                 CC|                            |jakub at gcc dot gnu.org
           Priority|P3                          |P2
            Summary|internal compiler error: in |[10/11 Regression] internal
                   |sign_mask, at               |compiler error: in
                   |wide-int.h:855              |sign_mask, at
                   |                            |wide-int.h:855
   Last reconfirmed|                            |2020-06-08
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r10-6527-gaaa26bf496a646778ac861aed124d960b5bf549f
Reduced testcase:

unsigned short
foo (unsigned short a)
{
  constexpr unsigned char b[1] = { 15 };
  return (0x00ffU & a) << b[0] | (0xff00U & a) >> b[0];
}

[Bug c++/95579] [10 Regression] internal compiler error: in sign_mask, at wide-int.h:855

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95579

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
            Summary|[10/11 Regression] internal |[10 Regression] internal
                   |compiler error: in          |compiler error: in
                   |sign_mask, at               |sign_mask, at
                   |wide-int.h:855              |wide-int.h:855
         Resolution|---                         |DUPLICATE

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, it has been fixed on the trunk already in
r11-474-g2d4e1e144c25e526e4f668be5a0bc10d0c1c738c

*** This bug has been marked as a duplicate of bug 94955 ***