Bug 2403472

Summary: GCC may miscompile AutoBuffer which causes Firefox crashes on Fedora 43 only.
Product: [Fedora] Fedora Reporter: Martin Stransky <stransky>
Component: gccAssignee: Jakub Jelinek <jakub>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 43CC: agurenko, dmalcolm, fweimer, jakub, jlaw, josmyers, jwakely, mcermak, mpolacek, msebor, nickc, nixuser, redhat, sam, sipoyare
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OS: Linux   
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Description Martin Stransky 2025-10-13 07:57:42 UTC 
Found upstream reports at https://bugzilla.mozilla.org/show_bug.cgi?id=1990430#c1

Firefox crash data at https://bugzilla.mozilla.org/show_bug.cgi?id=1990430 reports there are AutoBuffer array crashes on Fedora 43 only on all Firefox versions.

First crashes correlates with this GCC update: https://bodhi.fedoraproject.org/updates/FEDORA-2025-483b46505e 

This code may be wrongly align:
https://searchfox.org/firefox-main/rev/91e6069b9c1e7289d0c727b5110e144edc589204/xpcom/ds/nsTArray.h#2974


Reproducible: Always