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Bug 19313 - gcc miscompilation.
gcc miscompilation.
Product: Red Hat Linux
Classification: Retired
Component: gcc (Show other bugs)
i386 Linux
high Severity high
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Assigned To: Jakub Jelinek
David Lawrence
Depends On:
  Show dependency treegraph
Reported: 2000-10-18 08:09 EDT by David Woodhouse
Modified: 2005-10-31 17:00 EST (History)
0 users

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
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Clone Of:
Last Closed: 2000-10-24 04:28:05 EDT
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Regression: ---
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Verified Versions:
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oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Attachments (Terms of Use)
tarball containing gcc bug testcase. (4.50 KB, application/octet-stream)
2000-10-18 08:11 EDT, David Woodhouse
no flags Details

External Trackers
Tracker ID Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2000:132 normal SHIPPED_LIVE Bug fixing update of GCC 2.96 2000-12-19 00:00:00 EST

  None (edit)
Description David Woodhouse 2000-10-18 08:09:50 EDT
This code:

	cse = Variants[variant] ^ aTable2[variant];
	printf("Variants[%d] = 0x%2.2X, aTable2[%d] = 0x%2.2X\n",
		       variant, Variants[variant], variant, aTable2[variant]);
	printf("cse = 0x%2.2X\n", cse);

This output:

	Variants[4] = 0xCC, aTable2[4] = 0xDC
	cse = 0x73

/me tries to work out how to attach the testcase tarball..... sod it, it's

Compiling without -fomit-frame-pointer makes it better, as does compiling
with -O2 -fomit-frame-pointer -fschedule-insns. The tarball's makefile uses
the former to produce 'test-good'.
Comment 1 David Woodhouse 2000-10-18 08:11:15 EDT
Created attachment 4327 [details]
tarball containing gcc bug testcase.
Comment 2 Jakub Jelinek 2000-10-20 08:27:15 EDT
Thanks. Verified it happens with mainline CVS as well and is ia32 specific.
Will look into what's going on.
Comment 3 Jakub Jelinek 2000-10-24 04:27:58 EDT
Bernd Schmidt fixed this, the fix is in gcc-2.96-61.

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