[Bug middle-end/17308] nonnull attribute not as useful as it could

["msebor at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=17308

--- Comment #16 from Martin Sebor <msebor at gcc dot gnu.org> ---
Author: msebor
Date: Wed Dec 14 17:23:16 2016
New Revision: 243661

URL: https://gcc.gnu.org/viewcvs?rev=243661&root=gcc&view=rev
Log:
PR c/78673 - sprintf missing attribute nonnull on destination argument
PR c/17308 - nonnull attribute not as useful as it could be

gcc/ChangeLog:

        PR c/17308
        * builtin-attrs.def (ATTR_NONNULL_1_1, ATTR_NONNULL_1_2): Defined.
        (ATTR_NONNULL_1_3, ATTR_NONNULL_1_4, ATTR_NONNULL_1_5): Same.
        (ATTR_NOTHROW_NONNULL_1_1, ATTR_NOTHROW_NONNULL_1_2): Same.
        (ATTR_NOTHROW_NONNULL_1_3, ATTR_NOTHROW_NONNULL_1_4): Same.
        (ATTR_NOTHROW_NONNULL_1_5): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_1_2): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_2_0): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_2_3): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_3_0): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_3_4): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_4_0): Same.
        (ATTR_NONNULL_1_FORMAT_PRINTF_4_5): Same.
        * builtins.c (validate_arg): Add argument.  Treat null pointers
        passed to nonnull arguments as invalid.
        (validate_arglist): Same.
        * builtins.def (fprintf, fprintf_unlocked): Add nonnull attribute.
        (printf, printf_unlocked, sprintf. vfprintf, vsprintf): Same.
        (__sprintf_chk, __vsprintf_chk, __fprintf_chk, __vfprintf_chk): Same.
        * calls.c (get_nonnull_ags, maybe_warn_null_arg): New functions.
        (initialize_argument_information): Diagnose null pointers passed to
        arguments declared nonnull.
        * calls.h (get_nonnull_args): Declared.

gcc/c-family/ChangeLog:

        PR c/17308
        * c-common.c (check_nonnull_arg): Disable when optimization
        is enabled.

gcc/testsuite/ChangeLog:

        PR c/17308
        * gcc.dg/builtins-nonnull.c: New test.
        * gcc.dg/nonnull-4.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/builtins-nonnull.c
    trunk/gcc/testsuite/gcc.dg/nonnull-4.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/builtin-attrs.def
    trunk/gcc/builtins.c
    trunk/gcc/builtins.def
    trunk/gcc/c-family/ChangeLog
    trunk/gcc/c-family/c-common.c
    trunk/gcc/calls.c
    trunk/gcc/calls.h
    trunk/gcc/testsuite/ChangeLog