PATCH: Wconversion-sign

["Manuel López-Ibáñez" <lopezibanez at gmail dot com>]

:ADDPATCH diagnostics:

Some concerns have been raised about -Wconversion warning for
signed<->unsigned conversions. Although many users have asked for
warnings about those conversions, it is true that they are widespread
in real-world code. Thus, it has been requested to remove those
warnings from -Wconversion. Yet, I think that there is a group of
users that want to be warned about such conversions.

Therefore, the current patch moves signed<->unsigned conversions from
-Wconversion to a new option -Wconversion-sign. Warnings for a
negative value assigned to a unsigned variable are kept in
-Wconversion, since those were in Wconversion already and we haven't
received any complaints about it up to now (on the contrary, there
were some requests to implement them in C++).

Bootstrapped and regression tested.

OK for mainline?

2007-03-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>

 * doc/invoke.texi (Warning Options): Add -Wconversion-sign.
 (Wconversion): Update description.
 (Wconversion-sign): New.
 * c.opt (Wconversion-sign): New.
 * c-common.c (conversion_warning): Warn with either Wconversion or
Wconversion-sign.
 (warnings_for_convert_and_check): Likewise.

testsuite/
 * gcc.dg/Wconversion-integer.c: Move some warnings to Wconversion-sign.c
 * gcc.dg/Wconversion-sign.c: New.
 * g++.dg/warn/Wconversion-integer.C: Move some warnings to Wconversion-sign.C
 * g++.dg/warn/Wconversion-sign.C: New.

Attachment: wconversion-sign-try2.diff
Description: Text document