Message-Id: <3.0.5.32.19980326112608.00a59950@hal.nt.tuwien.ac.at>
Date: Thu, 26 Mar 1998 11:26:08 +0100
To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
From: Anton Helm <tony AT nt DOT tuwien DOT ac DOT at>
Subject: Re: flex never frees some buffers !?
Cc: djgpp AT delorie DOT com
In-Reply-To: <Pine.SUN.3.91.980326130521.835B-100000@is>
References: <3 DOT 0 DOT 5 DOT 32 DOT 19980326093933 DOT 00a57c10 AT hal DOT nt DOT tuwien DOT ac DOT at>
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At 13:07 26.03.98 +0300, you wrote:
>
>On Thu, 26 Mar 1998, Anton Helm wrote:
>
>> The yy_delete_buffer works fine for additionally aquired buffers
>> (e.g. if you parse included files, like *.h in C) but NOT for the
>> initial buffer because you are still inside flex when you detect
>> an EOF and obviously must leave yylex() before freeing memory.

>But your problem was, as I recall it, that Flex was using up 16K
>*per buffer*.  yy_delete_buffer should be the solution for n-1 buffers 
>out of n, at the least.  

Sorry for my beeing inprecise.
I mean:
I have a program.exe that reads n different files with n
different flex/bison parsers(e.g. aalex(), bblex(), cclex(), ...)
each of them consuming at least 16k.
Any of the n files may contain any number m of (nested) "include" 
statements. The buffers for these m flex inputs can be freed
with yy_delete_buffer. But not the n initial buffers.
A typical number from one of our projects is 9 parsers per *.exe
which means 144k memory waste.

>Surely, any modern machine can afford allocating 
>16KB, no?

Not any bit.
I'm not writing Micros*** programs :-)

Tony






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