Date: 11 Sep 1997 21:07:31 +0200 From: Peter Mutsaers <plm@xs4all.nl> To: markm@iafrica.com, freebsd-bugs@freebsd.org Subject: Re: gnu/4511: GCC optimization broken with -m486? Message-ID: <874t7rd5zg.fsf@muon.xs4all.nl> In-Reply-To: Mark R V Murray's message of Thu, 11 Sep 1997 12:23:40 %2B0200 (SAT) References: <199709111023.MAA27219@rodent.iafrica.com>
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>> On Thu, 11 Sep 1997 12:23:40 +0200 (SAT), Mark R V Murray
>> <markm@iafrica.com> said:
>> Description:
MRVM> We noticed this problem when sh(1) started to misbehave.
MRVM> sh objects to a line in a script that looks like
MRVM> foo=$((2 << 29))
>> How-To-Repeat:
MRVM> [make 2.2-STABLE with CFLAGS in /etc/make.conf as above]
MRVM> cd /dev ; ./MAKEDEV
>> Fix:
MRVM> Workarounds:
MRVM> 1) remove 1 of -O2 or -m486
MRVM> 2) modify the offending line in the script to read
MRVM> foo=$((2<<29))
MRVM> (ie remove the spaces on either side of <<)
I always build using -O2 and -m486, and my -current sh does not show
this bug.
By the way, in another follow-up Bruce Evans said that -m486 should
not be used and doesn't improve things. Is that really true? According
to gcc's man page it should improve speed for a 486, so I assumed it
will benefit a Pentium too.
--
/\_/\
( o.o ) Peter Mutsaers | Abcoude (Utrecht), | Trust me, I know
) ^ ( plm@xs4all.nl | the Netherlands | what I'm doing.
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