[Bug c/102245] New: false int-in-bool-context warning with shift

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102245

            Bug ID: 102245
           Summary: false  int-in-bool-context warning with shift
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
#define shiftCB_DISABLE_FAULT_ON_UNMAPPED_ACCESS1 0
#define maskCB_DISABLE_FAULT_ON_UNMAPPED_ACCESS1 1L

#define REG_FIELD_MASK(a,b) (mask##b)
#define REG_FIELD_SHIFT(a,b) (shift##b)

#define REG_SET_FIELD(orig_val, reg, field, field_val)                  \
        (((orig_val) & ~REG_FIELD_MASK(reg, field)) |                   \
         (REG_FIELD_MASK(reg, field) & ((field_val) << REG_FIELD_SHIFT(reg,
field))))



int f(_Bool enable)
{
  int tmp = 0;
  tmp = REG_SET_FIELD(tmp, VM_PRT_CNTL,
                      CB_DISABLE_FAULT_ON_UNMAPPED_ACCESS1,
                      enable);
  return tmp;
}

------ CUT ----
Compile this on an ILP32 target with "-W -Wall -O2 -Werror
-Werror=int-in-bool-context" and you get:
<source>: In function 'f':
<source>:10:53: error: '<<' in boolean context, did you mean '<'?
[-Werror=int-in-bool-context]
   10 |          (REG_FIELD_MASK(reg, field) & ((field_val) <<
REG_FIELD_SHIFT(reg, field))))
      |                                       
~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
<source>:17:9: note: in expansion of macro 'REG_SET_FIELD'
   17 |   tmp = REG_SET_FIELD(tmp, VM_PRT_CNTL,
      |         ^~~~~~~~~~~~~
cc1: all warnings being treated as errors


This is not correct as the shift is correct, I want to do a shift by 0 here and
there is no boolean context at all. And it does not warn with LP64 targets
either.