Re: PATCH RFA: Tweak vec.[ch] to avoid undefined signed overflow

[Nathan Sidwell <nathan at codesourcery dot com>]

Ian Lance Taylor wrote:

> There is no major issue here.  But after some discussion and some
> thought, I think this code should stop overloading negative values,
> and simply use a different function when it needs to reserve an exact
> size.  I think this is slightly easier to understand and slightly more
> efficient.
>
> This patch passes bootstrap and testsuite run on i686-pc-linux-gnu.
> OK for mainline?

ok.  I do have a bad tendency for such 'cute' overloads :)

> gcc/ChangeLog:
> 2007-01-16  Ian Lance Taylor  <iant@google.com>
>
> 	* vec.h (VEC_reserve_exact): Define.
> 	(vec_gc_p_reserve_exact): Declare.
> 	(vec_gc_o_reserve_exact): Declare.
> 	(vec_heap_p_reserve_exact): Declare.
> 	(vec_heap_o_reserve_exact): Declare.
> 	(VEC_OP (T,A,reserve_exact)): New static inline function, three
> 	versions.
> 	(VEC_OP (T,A,reserve)) [all versions]: Remove handling of
> 	negative parameter.
> 	(VEC_OP (T,A,alloc)) [all versions]: Call ...reserve_exact.
> 	(VEC_OP (T,A,copy)) [all versions]: Likewise.
> 	(VEC_OP (T,a,safe_grow)) [all versions]: Likewise.
> 	* vec.c (calculate_allocation): Add exact parameter.  Change all
> 	callers.
> 	(vec_gc_o_reserve_1): New static function, from vec_gc_o_reserve.
> 	(vec_gc_p_reserve, vec_gc_o_reserve): Call vec_gc_o_reserve_1.
> 	(vec_gc_p_reserve_exact, vec_gc_o_reserve_exact): New functions.
> 	(vec_heap_o_reserve_1): New static function, from vec_heap_o_reserve.
> 	(vec_heap_p_reserve, vec_heap_o_reserve): Call vec_heap_o_reserve_1.
> 	(vec_heap_p_reserve_exact): New function.
> 	(vec_heap_o_reserve_exact): New function.
>
> gcc/cp/ChangeLog:
> 2007-01-16  Ian Lance Taylor  <iant@google.com>
>
> 	* class.c (add_method): Call VEC_reserve_exact rather than passing
> 	a negative size to VEC_reserve.


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nathan@codesourcery.com    ::     http://www.planetfall.pwp.blueyonder.co.uk