[Bug c/57200] New: [4.8/4.9] aggressive-loop-optimizations notes appear even when warning itself is suppressed

[ppluzhnikov at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57200

             Bug #: 57200
           Summary: [4.8/4.9] aggressive-loop-optimizations notes appear
                    even when warning itself is suppressed
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: ppluzhni...@google.com


Test:

int x[10];

void fn ()
{
  int i;

  for (i = 0; i < 100; ++i)
    x[i] = 1;
}


Using trunk at r198689:

gcc -O2 -c t.c 
t.c: In function ‘fn’:
t.c:8:10: warning: iteration 10u invokes undefined behavior
[-Waggressive-loop-optimizations]
     x[i] = 1;
          ^
t.c:7:3: note: containing loop
   for (i = 0; i < 100; ++i)
   ^


Looks good. But this doesn't:

gcc -O2 -c t.c -w
t.c: In function ‘fn’:
t.c:7:3: note: containing loop
   for (i = 0; i < 100; ++i)
   ^

A note suddenly appears from "nowhere" :-(