[LLVMbugs] [Bug 11536] New: Clang incorrect array-bounds warning on strpbrk in GlibC 2.9 header

[bugzilla-daemon at llvm.org]

http://llvm.org/bugs/show_bug.cgi?id=11536

             Bug #: 11536
           Summary: Clang incorrect array-bounds warning on strpbrk in
                    GlibC 2.9 header
           Product: clang
           Version: trunk
          Platform: PC
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P
         Component: Static Analyzer
        AssignedTo: kremenek at apple.com
        ReportedBy: pdox at google.com
                CC: llvmbugs at cs.uiuc.edu
    Classification: Unclassified


Created attachment 7710
  --> http://llvm.org/bugs/attachment.cgi?id=7710
example code

Compile the attached example.c with Clang. The code was taken from
bits/string2.h in GlibC 2.9. It appears to be correct.

$ clang example.c -Werror

example.c:26:26: error: array index 2 is past the end of the array
      (which contains 2 elements) [-Werror,-Warray-bounds]
  foo = strpbrk("hello", "l");
        ~~~~~~~~~~~~~~~~~^~~~
example.c:16:46: note: expanded from macro 'strpbrk'
               : ((__a2 = ((__const char *) (accept))[2], __a2 == '\0')       \
                                             ^        ~
example.c:26:26: error: array index 3 is past the end of the array
      (which contains 2 elements) [-Werror,-Warray-bounds]
  foo = strpbrk("hello", "l");
        ~~~~~~~~~~~~~~~~~^~~~
example.c:18:41: note: expanded from macro 'strpbrk'
                  : (((__const char *) (accept))[3] == '\0'                   \
                                        ^        ~
2 errors generated.

-- 
Configure bugmail: http://llvm.org/bugs/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.