[Bug sanitizer/95496] New: [10/11 Regression] Bogus -Wformat-overflow= warnings with -fsanitize=undefined

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95496

            Bug ID: 95496
           Summary: [10/11 Regression] Bogus -Wformat-overflow= warnings
                    with -fsanitize=undefined
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hjl.tools at gmail dot com
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org, marxin at gcc dot gnu.org
  Target Milestone: ---

Created attachment 48666
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48666&action=edit
A testcase

GCC 10.1 gave

[hjl@gnu-cfl-2 tmp]$ gcc -Wall -S -O2 x.i -fsanitize=undefined
In function ‘pe_print_idata’,
    inlined from ‘_bfd_pe_print_private_bfd_data_common’ at peXXigen.c:2979:3:
peXXigen.c:1378:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1378:3: warning: null format string [-Wformat-overflow=]
In function ‘pe_print_edata’,
    inlined from ‘_bfd_pe_print_private_bfd_data_common’ at peXXigen.c:2980:3:
peXXigen.c:1713:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1719:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1716:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1719:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1719:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1737:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1744:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1740:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1744:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1744:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1747:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1750:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1750:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1755:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1760:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1760:3: warning: null format string [-Wformat-overflow=]
peXXigen.c:1760:3: warning: null format string [-Wformat-overflow=]
[hjl@gnu-cfl-2 tmp]$ 

GCC 9.3 is OK.