483956 - gcc 4.4 warnings about "may be undefined" operations

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Wolfgang Rosenauer [:wolfiR]]

jstracer.cpp: In function 'bool isPromoteInt(nanojit::LIns*)':
jstracer.cpp:624: warning: operation on 'd' may be undefined
jstracer.cpp: In function 'bool isPromoteUint(nanojit::LIns*)':
jstracer.cpp:631: warning: operation on 'd' may be undefined

Comment 1

[Wolfgang Rosenauer [:wolfiR]]

On a sidenote I'm a bit confused as jstracer.cpp is not compiled on x86-64 Linux apparently

Comment 2

[Jeff Walden [:Waldo]]

Hm, this is pretty bad actually -- we're relying on spec-undefined left-then-right order of evaluation for ==.  Presumably every compiler we've tested against is doing left-then-right, else we'd have had crashes in tests, but this is going to bite us eventually if we keep relying on it.

Comment 3

[Jeff Walden [:Waldo]]

Attachment: Patch

Comment 4

[Jeff Walden [:Waldo]]

jstracer.cpp isn't compiled on x86-64 because JIT isn't going to be supported in 64-bit builds for a little while; with no official 64-bit release and fairly few people running 64-bit OSes it didn't make sense to put special effort into 64-bit right now.

Comment 5

[Jeff Walden [:Waldo]]

http://hg.mozilla.org/tracemonkey/rev/2b3812472561

Comment 6

[Robert Sayre]

http://hg.mozilla.org/mozilla-central/rev/2b3812472561

Comment 7

[Robert Sayre]

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/fe6ca1602c9d