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Bug 1055613

Summary: glibc scanf bug, breaks ATLAS build
Product: [Fedora] Fedora Reporter: Volker Braun <>
Component: glibcAssignee: Siddhesh Poyarekar <spoyarek>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 20CC: codonell, fweimer, jakub, law, mnewsome, pfrankli, spoyarek
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Fixed In Version: glibc-2.18-12.fc20 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-02-01 04:03:26 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Volker Braun 2014-01-20 15:50:03 UTC
Description of problem:

Glibc fails to parse 0 in scientific notation. This breaks the ATLAS build system, failing with a segfault in RunMADef (atlas-3.8.4) or an assertion failure in RunMulAdd (atlas-3.10.1).

Version-Release number of selected component (if applicable): 
* Fedora 20
* glibc-devel-2.18-11.fc20

How reproducible:


Steps to Reproduce:

$ cat test.c 
#include <stdio.h>
int main() {
    float a, b;
    int r = sscanf("0e+0 42", "%f %f", &a, &b);
    printf("r=%d a=%f b=%f\n", r, a, b);
    return 0;

Actual results:

$ gcc test.c && ./a.out
r=1 a=0.000000 b=0.000000

Expected results:

r=2 a=0.000000 b=42.000000

Additional info:

Comment 1 Carlos O'Donell 2014-01-20 16:30:38 UTC

Thanks. Sorry about this. We'll get this fixed ASAP.


Would you mind looking at the backport?

Comment 2 Fedora Update System 2014-01-30 10:14:50 UTC
glibc-2.18-12.fc20 has been submitted as an update for Fedora 20.

Comment 3 Fedora Update System 2014-01-31 04:26:12 UTC
Package glibc-2.18-12.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing glibc-2.18-12.fc20'
as soon as you are able to.
Please go to the following url:
then log in and leave karma (feedback).

Comment 4 Fedora Update System 2014-02-01 04:03:26 UTC
glibc-2.18-12.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.