scope of malloc

[Richard Tobin]

In article <14413 at smoke.brl.mil> gwyn at smoke.brl.mil (Doug Gwyn) writes:

>>You have the choice of rejecting machines or compilers with such serious
>>deficiencies as making alloca() impossible.

>What nonsense.  Being unlike a VAX is hardly a "serious deficiency".

As you know, there are plenty of machines that are quite unlike vaxes
that implement alloca().  I think you would even agree that there are
very few machines on which it is impossible.  So I think your comment
is pointless.

To return to the technical point, it is certainly true that it's hard
to implement alloca() efficiently *as a normal function* on several
processors.  An increasing number of compilers recognise alloca() as a
special case (typically #defining it as __builtin_alloca).  Sun's C
compiler and gcc are examples.  Are there *any* widely-used processors
that can't implement alloca() reasonably efficiently even with
compiler support?

-- Richard

-- 
Richard Tobin,                       JANET: R.Tobin at uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed at nsfnet-relay.ac.uk
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