[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]

      |                         ^

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with preprocessed source if appropriate.

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

Compiler returned: 1