PATCH: gengtype-lex.l warning

Kaveh R. Ghazi
Tue Jan 6 20:02:00 GMT 2009

From: "Kaveh R. Ghazi" <>

> There is a claim here:
> that flex-2.5.33 produces signed/unsigned warnings, but I don't see that. 
> (It may be that the distribution I use fixed things locally.)

I built vanilla flex 2.5.{33,34,35} on an x86_64-linux-gnu box to see what's 
the status vs using it in GCC.  They all seem to build the gt-*.h files 
fine, and I don't see any differences in the contents using diff as compared 
to the system flex.

However all three vanilla versions of flex produce a signed/unsigned warning 
in gengtype-lex.c.  So the system flex on my box has fixed the warning 

In addition, versions .33 and .34 still have the missing prototype warnings. 
The .35 version has those fixed at least.

My conclusion is that we cannot remove the -Wno-error yet, even with the 
latest version of flex.  However if someone needs a feature only available 
in these later versions, there doesn't seem to be any technical reason to 
prohibit upgrading the minimum required version of flex required by GCC. 
They all work fine.


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