Bug 164805

Summary: gcc -Os generates bad assembler code
Product: Red Hat Enterprise Linux 4 Reporter: Elena Zannoni <ezannoni>
Component: gccAssignee: Jakub Jelinek <jakub>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 4.0   
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard:
Fixed In Version: RHBA-2005-677 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2005-10-05 11:18:10 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 154116    
Bug Blocks: 156322    

Description Elena Zannoni 2005-08-01 16:04:38 UTC 
+++ This bug was initially created as a clone of Bug #154116 +++

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Description of problem:
For the included example, gcc generates assembler code that makes the assembler
complain.  The assembler code uses an immediate value in a movb that does not
fit in a byte.  The original C code does not do this.

Version-Release number of selected component (if applicable):
gcc-3.4.2-6.fc3

How reproducible:
Always

Steps to Reproduce:
1. fetch attached file "gcc-inline-bad-byte.c"
2. gcc -Os -c gcc-inline-bad-byte.c
  

Actual Results:  /tmp/ccDdmcnm.s: Assembler messages:
/tmp/ccDdmcnm.s:9: Warning: 277 shortened to 21


Expected Results:  no error messages

Additional info:

This example is boiled down from driver code being developed by the ivtv project.
Without inlining, there is no bad assembler code (I presume that the resulting
code is correct, but I have not looked).
Comment 1 Tom Kincaid 2005-08-02 11:06:08 UTC 
QE-ACK
Comment 2 Red Hat Bugzilla 2005-10-05 11:18:10 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2005-677.html