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Re: [tree-ssa] dead const/pure/alloca call removal
Falk Hueffner <falk.hueffner@student.uni-tuebingen.de> writes:
> "Zack Weinberg" <zack@codesourcery.com> writes:
>
>> I don't know what the right thing is, but I'd point out that this
>> optimization applies to all functions whose side effect is to
>> allocate a new block of memory, the sole pointer to which is
>> returned. malloc and calloc (but not realloc) are the obvious
>> examples.
>
> No, they set errno.
Yah, but an s.c. program cannot make any assumptions about the value
of errno unless it has just called a library function and observed it
to fail, so if the return value of malloc is ignored, the call to
malloc can safely be deleted.
zw