[Bug libquadmath/99202] New: Undefined behaviour in libquadmath file rem_pio2q.c function __quadmath_rem_pio2q

[zeccav at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99202

            Bug ID: 99202
           Summary: Undefined behaviour in libquadmath file rem_pio2q.c
                    function __quadmath_rem_pio2q
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libquadmath
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zeccav at gmail dot com
  Target Milestone: ---

! from dec_math.f90 
! must be compiled and run
! gfortran compiler needs not be sanitized
! must load sanitized libquadmath.so.0 as in ldd a.out -> libquadmath.so.0 =>
/home/vitti/local/gcc-150221-undefined/lib64/libquadmath.so.0
! ../../../gcc-150221/libquadmath/math/rem_pio2q.c:562:26: runtime error: left
shift of 4612846647631955497 by 23 places cannot be represented in type 'long
int'
! rem_pio2q.c:562 -> "tx [2] = (double)(((ix << 23) | (lx >> 41)) & 0xffffff);"
      real(16) :: q_i1,  q_oa

      q_i1 = 34.3774677078493908766176900826395_16

      q_oa = cotan (q_i1)

      end