[Bug target/95637] New: Read-only data assigned to `.sdata' rather than `.rodata'

[ma...@linux-mips.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95637

            Bug ID: 95637
           Summary: Read-only data assigned to `.sdata' rather than
                    `.rodata'
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ma...@linux-mips.org
  Target Milestone: ---
            Target: riscv*-*-linux-gnu

As observed in PR fortran/95631 read-only data gets assigned to `.sdata'
rather than `.rodata', which in turn causes invalid attempts to modify it
not to be trapped at run time.

A test case from the PR referred is:

C
C     CHANGE THE VALUE OF 4
C

      CALL INC(4)
      WRITE (*, 30) 4
30    FORMAT ('2+2=',I4)
      END

      SUBROUTINE INC(I)
      I = I + 1
      END

which is supposed to trap on the modification of literal 4 in INC.
Instead the program runs to completion and prints:

2+2=   5

I have no C language test case at hand, but I guess it does not matter,
this one is sweet and simple.