850935 - Helgrind warnings about data races on multiple global/static variables when multiple runtimes are used (e.g. DOM Workers)

Status: RESOLVED INCOMPLETE

(Core :: JavaScript Engine, defect)

Description

[Ben Turner (not reading bugmail, use the needinfo flag!)]

==3013== Possible data race during write of size 8 at 0xAC75358 by thread #10
==3013== Locks held: none
==3013==    at 0x8BC593C: js::InitRuntimeNumberState(JSRuntime*) (jsnum.cpp:1034)
==3013==    by 0x89993AC: JSRuntime::init(unsigned int) (jsapi.cpp:922)
==3013==    by 0x89BA190: JS_NewRuntime(unsigned int, JSUseHelperThreads) (jsapi.cpp:1127)
==3013== This conflicts with a previous write of size 8 by thread #9
==3013== Locks held: none
==3013==    at 0x8BC593C: js::InitRuntimeNumberState(JSRuntime*) (jsnum.cpp:1034)
==3013==    by 0x89993AC: JSRuntime::init(unsigned int) (jsapi.cpp:922)
==3013==    by 0x89BA190: JS_NewRuntime(unsigned int, JSUseHelperThreads) (jsapi.cpp:1127)

There are several more in jsnum.cpp right after this. They look like harmless redundant writes of the same value, but someone who knows this code better should double check.

==3013== Possible data race during write of size 8 at 0xAC753B8 by thread #10
==3013== Locks held: none
==3013==    at 0x8C5EA1B: js::Probes::createRuntime(JSRuntime*) (jsprobes.cpp:114)
==3013==    by 0x89BA1BC: JS_NewRuntime(unsigned int, JSUseHelperThreads) (jsapi.cpp:1132)
==3013== This conflicts with a previous write of size 8 by thread #9
==3013== Locks held: none
==3013==    at 0x8C5EA1B: js::Probes::createRuntime(JSRuntime*) (jsprobes.cpp:114)
==3013==    by 0x89BA1BC: JS_NewRuntime(unsigned int, JSUseHelperThreads) (jsapi.cpp:1132)

This looks unused and should probably be removed altogether.