Ping?
Mark
On Fri, Aug 12, 2011 at 9:41 AM, Mark Heffernan <meh...@google.com> wrote:
> This patch adds an option for enabling/disabling the warning for
> attempting to free nonheap objects (PR/38509). The warning is
> imprecise and can issue false positives.
>
> Bootstrapped on x86-64. Ok for trunk?
>
> Mark
>
> 2011-08-11 Mark Heffernan <meh...@google.com>
>
> PR middle-end/38509
> * common.opt (Wfree-nonheap-object): New option.
> * doc/invoke.texi (Warning options): Document -Wfree-nonheap-object.
> * builtins.c (maybe_emit_free_warning): Add OPT_Wfree_nonheap_object
> to warning.
>
>
>
> Index: gcc/doc/invoke.texi
> ===================================================================
> --- gcc/doc/invoke.texi (revision 177684)
> +++ gcc/doc/invoke.texi (working copy)
> @@ -244,7 +244,8 @@ Objective-C and Objective-C++ Dialects}.
> -Wfatal-errors -Wfloat-equal -Wformat -Wformat=2 @gol
> -Wno-format-contains-nul -Wno-format-extra-args -Wformat-nonliteral @gol
> -Wformat-security -Wformat-y2k @gol
> --Wframe-larger-than=@var{len} -Wjump-misses-init -Wignored-qualifiers @gol
> +-Wframe-larger-than=@var{len} -Wno-free-nonheap-object -Wjump-misses-init
> @gol
> +-Wignored-qualifiers @gol
> -Wimplicit -Wimplicit-function-declaration -Wimplicit-int @gol
> -Winit-self -Winline -Wmaybe-uninitialized @gol
> -Wno-int-to-pointer-cast -Wno-invalid-offsetof @gol
> @@ -3960,6 +3961,12 @@ via @code{alloca}, variable-length array
> is not included by the compiler when determining
> whether or not to issue a warning.
>
> +@item -Wno-free-nonheap-object
> +@opindex Wno-free-nonheap-object
> +@opindex Wfree-nonheap-object
> +Do not warn when attempting to free an object which was not allocated
> +on the heap.
> +
> @item -Wstack-usage=@var{len}
> @opindex Wstack-usage
> Warn if the stack usage of a function might be larger than @var{len} bytes.
>
> Index: gcc/builtins.c
> ===================================================================
> --- gcc/builtins.c (revision 177684)
> +++ gcc/builtins.c (working copy)
> @@ -6087,7 +6087,8 @@ expand_builtin (tree exp, rtx target, rt
> break;
>
> case BUILT_IN_FREE:
> - maybe_emit_free_warning (exp);
> + if (warn_free_nonheap_object)
> + maybe_emit_free_warning (exp);
> break;
>
> default: /* just do library call, if unknown builtin */
> @@ -11863,11 +11864,11 @@ maybe_emit_free_warning (tree exp)
> return;
>
> if (SSA_VAR_P (arg))
> - warning_at (tree_nonartificial_location (exp),
> - 0, "%Kattempt to free a non-heap object %qD", exp, arg);
> + warning_at (tree_nonartificial_location (exp), OPT_Wfree_nonheap_object,
> + "%Kattempt to free a non-heap object %qD", exp, arg);
> else
> - warning_at (tree_nonartificial_location (exp),
> - 0, "%Kattempt to free a non-heap object", exp);
> + warning_at (tree_nonartificial_location (exp), OPT_Wfree_nonheap_object,
> + "%Kattempt to free a non-heap object", exp);
> }
>
> /* Fold a call to __builtin_object_size with arguments PTR and OST,
> Index: gcc/common.opt
> ===================================================================
> --- gcc/common.opt (revision 177684)
> +++ gcc/common.opt (working copy)
> @@ -543,6 +543,10 @@ Wframe-larger-than=
> Common RejectNegative Joined UInteger
> -Wframe-larger-than=<number> Warn if a function's stack frame
> requires more than <number> bytes
>
> +Wfree-nonheap-object
> +Common Var(warn_free_nonheap_object) Init(1) Warning
> +Warn when attempting to free a non-heap object
> +
> Winline
> Common Var(warn_inline) Warning
> Warn when an inlined function cannot be inlined
>
