| Message ID | CAOi2v+RcJo4m1az+KLGTWfN7zg=Rme+Qdi+WiMXCDCj2z+jdfA@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
Ping? Mark On Fri, Aug 12, 2011 at 9:41 AM, Mark Heffernan <meheff@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 <meheff@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 >
On 11-08-21 18:14 , Mark Heffernan wrote: > Ping? > > Mark > > On Fri, Aug 12, 2011 at 9:41 AM, Mark Heffernan<meheff@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<meheff@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. OK. Diego.
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