[PATCH INSTALLED]: Fix -Wc++-compat warnings in toplevel [t-z]*.c files

[Andrew Haley]

Gabriel Dos Reis wrote:
>> Even with -Wall we get no warnings.
>
> That is correct; however, what that suggests is care needs
> to be exercised when writing allocation, and that has always
> been so (whether we make the code compilable with a C++
> compiler or not).  In fact, the use of libiberty allocator-like
> macros makes this issue go away.

Indeed, yes.

>> Is this error unlikely?  I don't think so.
>
> Have you found any instance in GCC codebase, or any of
> Kaveh's patch?

It's only been a couple of days!  Every time you cast a pointer you're
punching a hole in the type system.  Every such cast removes some of
the useful type checking done by the compiler.  Both of us know this:
to declare that we don't need this would be to suggest that gcc
maintainers are as gods, untainted by the errors of mere mortals.
But I'm sure you're not suggesting such a thing.

There is no doubt, at least in my mind, that the quality and
reliability of the code, considered as pure C, will be degraded by
adding pointer casts in many placed.  If we can adopt practices such
as libiberty allocator-like macros wherever possible, and make sure
that the cast is not removed from the preprocessed source when using
the C front end, that will surely help.

Andrew.