Opened 5 years ago

Closed 2 years ago

#13436 closed defect (wontfix)

Tor Browser 4.0 crashes with SIGILL

Reported by: torar Owned by: tbb-team
Priority: Medium Milestone:
Component: Applications/Tor Browser Version:
Severity: Normal Keywords:
Cc: Actual Points:
Parent ID: Points:
Reviewer: Sponsor:


Tor Browser 4.0 crashes with SIGILL on AMD K6 or Pentium processors. These processors do not have the CMOV instruction and Tor Browser 4.0 was compiled with CMOV.

Tor Browser 3.6.6 and previous versions work well on processors without CMOV.

Please, recompile the Tor Browser with -march=i586, so that it uses instruction set of 586 processors.

Child Tickets

Change History (6)

comment:1 Changed 5 years ago by gk

Vanilla Firefox ESR is working for you? Which OS/architecture?

comment:2 in reply to:  1 Changed 5 years ago by yawning

Replying to gk:

Vanilla Firefox ESR is working for you? Which OS/architecture?

This would be i386 Linux, because Windows doesn't send SIGILL. and the processors the user is complaining about are circa the late 90s (and aren't 64 bit).

I'm not sure what assumptions Mozilla makes about "how new your x86 processor is" when compiling official binaries, though the recommended CPU on the page is "Pentium 4 with SSE2 support".

IMO: I'd assume the users of pre-Athlon AMD, pre-Pentium II Intel, pre-Nehemiah VIA, and pre-NX AMD Geode are a tiny minority, and backwards compatibility has to end somewhere. Then again working around the existence of processors with this particular form of brain damage would just be a Linux 32 bit thing.

comment:3 Changed 5 years ago by torar

It doesn't depend on Mozilla source code - it depends on how you compile it. If you compile it with CFLAGS=-march=i586, it will work on 586 CPUs, with CFLAGS=-march=i686 it won't.

Firefox from Debian works for me (because Debian compiles almost packages with -march=i586). Tor Browser 3.6 was compiled in such a way that it worked on 586 CPUs. All you need to do is to use a proper flag to the compiler.

comment:4 Changed 4 years ago by cypherpunks_backup

Keywords: tbb-crash added
Severity: Normal
Status: newneeds_information

comment:5 Changed 4 years ago by bugzilla

Keywords: tbb-crash removed

There are no plans to compile with -march=i586, so:
Propose closing as INVALID.

comment:6 Changed 2 years ago by gk

Resolution: wontfix
Status: needs_informationclosed
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