On 16/01/2014 03:45, Jonathan Wakely wrote:
> On 16 January 2014 11:11, Sylvestre Ledru wrote:
>> Hello,
>>
>> On 17/11/2013 17:47, Jonathan Wakely wrote:
>>> On 17 November 2013 15:40, Sylvestre Ledru wrote:
>>>> For "control reaches end of non-void function", I haven't activated by
>>>> default and I called the option -Wfalloff-nonvoid-function
>>>> Of course, that is just a proposal! :) Better names are welcome.
>>> It was nearly called -Wmissing-return a decade ago, but got bundled
>>> with -Wreturn-type, see
>>> http://gcc.gnu.org/ml/gcc-patches/2002-02/msg02002.html
>> As discussed on this mailing list, I proposed a patch on the gcc-patches
>> mailing list.
>> http://gcc.gnu.org/ml/gcc-patches/2014-01/msg00820.html
>>
>> Any chance one of you could review it?
> I like the change in principle, but it's not up to me, I can't approve
> front-end patches. I can comment on the docs and ChangeLog but I'm
> not subscribed to gcc-patches so didn't get the mail. I'll send some
> comments, could you please reply to your gcc-patches mail and include
> my comments? Thanks.
Following the comments you sent me, here it is:
> Does -Wreturn-type enable -Wmissing-return? If not, users who
> currently use -Werror=return-type might be surprised when "missing
> return" warnings are no longer errors., because they are controlled by
> a different option. That would require users to add
> -Werror=missing-return to their makefiles, which would not be
> compatible with older versions of GCC.
Actually, I wonder if -Wmissing-return should not be included by default ...
If you do not agree, could you tell me how I could enable
-Wmissing-return with both
-Wreturn-type and -Wall?
Now, the code (I haven't touched the testsuite, the archive remains the
same).
gcc/ChangeLog:
2014-01-23 Sylvestre Ledru <sylves...@debian.org>
PR other/PR55189
* doc/invoke.texi: Update of the documentation (-Wreturn-type
-Wmissing-return enabled by default)
* tree-cfg.c: Likewise
gcc/c-family/ChangeLog:
2014-01-23 Sylvestre Ledru <sylves...@debian.org>
* c.opt: Extract -Wmissing-return from -Wreturn-type to return
a warning when a return statement is missing.
gcc/fortran/ChangeLog:
2014-01-23 Sylvestre Ledru <sylves...@debian.org>
* options.c: Extract -Wmissing-return from -Wreturn-type to return
a warning when a return statement is missing.
Index: gcc/c-family/c.opt
===================================================================
--- gcc/c-family/c.opt (révision 206953)
+++ gcc/c-family/c.opt (copie de travail)
@@ -673,9 +673,13 @@
Warn about returning a pointer/reference to a local or temporary variable.
Wreturn-type
-C ObjC C++ ObjC++ Var(warn_return_type) Warning LangEnabledBy(C ObjC
C++ ObjC++,Wall)
+C ObjC C++ ObjC++ Var(warn_return_type) Init(1) Warning
Warn whenever a function's return type defaults to \"int\" (C), or
about inconsistent return types (C++)
+Wmissing-return
+C ObjC C++ ObjC++ Var(warn_missing_return) Init(1) Warning
LangEnabledBy(C ObjC C++ ObjC++, Wreturn-type)
+Warn whenever control may reach end of non-void function
+
Wselector
ObjC ObjC++ Var(warn_selector) Warning
Warn if a selector has multiple methods
Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi (révision 206953)
+++ gcc/doc/invoke.texi (copie de travail)
@@ -255,7 +255,7 @@
-Winvalid-pch -Wlarger-than=@var{len} -Wunsafe-loop-optimizations @gol
-Wlogical-op -Wlong-long @gol
-Wmain -Wmaybe-uninitialized -Wmissing-braces
-Wmissing-field-initializers @gol
--Wmissing-include-dirs @gol
+-Wmissing-include-dirs -Wmissing-return @gol
-Wno-multichar -Wnonnull -Wno-overflow -Wopenmp-simd @gol
-Woverlength-strings -Wpacked -Wpacked-bitfield-compat -Wpadded @gol
-Wparentheses -Wpedantic-ms-format -Wno-pedantic-ms-format @gol
@@ -3348,6 +3348,7 @@
-Wmain @r{(only for C/ObjC and unless} @option{-ffreestanding}@r{)} @gol
-Wmaybe-uninitialized @gol
-Wmissing-braces @r{(only for C/ObjC)} @gol
+-Wmissing-return @gol
-Wnonnull @gol
-Wopenmp-simd @gol
-Wparentheses @gol
@@ -3810,7 +3811,11 @@
message, even when @option{-Wno-return-type} is specified. The only
exceptions are @samp{main} and functions defined in system headers.
-This warning is enabled by @option{-Wall}.
+@item -Wmissing-return
+@opindex Wmissing-return
+@opindex Wno-missing-return
+Warn whenever falling off the end of the function body (i.e. without
+a return statement).
@item -Wswitch
@opindex Wswitch
Index: gcc/fortran/options.c
===================================================================
--- gcc/fortran/options.c (révision 206953)
+++ gcc/fortran/options.c (copie de travail)
@@ -717,6 +717,10 @@
warn_return_type = value;
break;
+ case OPT_Wmissing_return:
+ warn_missing_return = value;
+ break;
+
case OPT_Wsurprising:
gfc_option.warn_surprising = value;
break;
Index: gcc/tree-cfg.c
===================================================================
--- gcc/tree-cfg.c (révision 206953)
+++ gcc/tree-cfg.c (copie de travail)
@@ -8097,7 +8097,7 @@
/* If we see "return;" in some basic block, then we do reach the end
without returning a value. */
- else if (warn_return_type
+ else if (warn_missing_return
&& !TREE_NO_WARNING (cfun->decl)
&& EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds) > 0
&& !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
@@ -8112,7 +8112,7 @@
location = gimple_location (last);
if (location == UNKNOWN_LOCATION)
location = cfun->function_end_locus;
- warning_at (location, OPT_Wreturn_type, "control reaches end
of non-void function");
+ warning_at (location, OPT_Wmissing_return, "control reaches
end of non-void function");
TREE_NO_WARNING (cfun->decl) = 1;
break;
}
