c++/4898: adding an option to verify exception specifications

[Luc.Maisonobe@c-s.fr]

>Number:         4898
>Category:       c++
>Synopsis:       adding an option to verify exception specifications
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Mon Nov 19 03:26:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Luc Maisonobe
>Release:        gcc-3.0
>Organization:
>Environment:
All
>Description:
C++ allows to specify exceptions in the function declaration
but do not enforces it. When lots of classes and methods are
involved, maintaining up-to-date specifications is very
difficult, and every missed exception create runtime
problems (unexpected exception -> abort -> core dumped). For
the moment the lack of support tools prevents developers
from using these specifications effectively.

It would be very helpful to have a switch on the compiler
to get warnings if a function do not declare the exceptions
that can be thrown by itself and its callee and that are
either not caught or that are rethrown. This could be an
extension to the existing -Weffc++ flag.

As an example, one can look at Java that enforces the proper
declarations, this is nice.
>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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