I'm trying to build gjs against xulrunner 1.9.2 on Ubuntu, and seeing a test suite failure which only seems to affect i386. The log from the failure is here:

      JS CTX: Ignoring second exception: 'Second different exception foo'
      JS CTX: Enabling JIT
      JS CTX: Changing JavaScript version to 1.8 from default
      JS CTX: Creating load context for runtime 0x850ce68
      JS CTX: Enabling JIT
      JS CTX: Changing JavaScript version to 1.8 from default
   JS IMPORT: Initialized class GjsFileImporter prototype 0x8531720
   JS IMPORT: Defining parent 0x85313a0 of 0x8531740 'imports' is mod 0
   JS IMPORT: Defined importer 'imports' 0x8531740 in 0x85313a0
      JS CTX: Destroying JS context
      JS CTX: Clearing call context
      JS CTX: Call context cleared
      JS CTX: Clearing load context
      JS CTX: Destroying JS context (load context)
      JS CTX: Load context cleared
      JS CTX: Destroying JS runtime
      JS CTX: Destroying any remaining dataset items on runtime
      JS CTX: Enabling JIT
      JS CTX: Changing JavaScript version to 1.8 from default
      JS CTX: Creating load context for runtime 0x8096080
      JS CTX: Enabling JIT
      JS CTX: Changing JavaScript version to 1.8 from default
   JS IMPORT: Initialized class GjsFileImporter prototype 0x80bf720
   JS IMPORT: Defining parent 0x80bf3a0 of 0x80bf740 'imports' is mod 0
   JS IMPORT: Defined importer 'imports' 0x80bf740 in 0x80bf3a0
      JS CTX: Script evaluation succeeded
   JS IMPORT: JS import 'signals' not found in /tmp/buildd/gjs-0.5/_build/test/modules
   JS IMPORT: Importing '/tmp/buildd/gjs-0.5/_build/./modules/signals.js'
   JS IMPORT: Defining parent 0x80bf740 of 0x80bf8a0 'signals' is mod 1
   JS IMPORT: successfully imported module 'signals'
      JS LOG: running test testSimple
      JS LOG: Received signal 'bar'
      JS LOG: running test testDisconnectDuringEmit
      JS LOG: Received signal 'bar', disconnecting others
      JS LOG: running test testMultipleSignals
      JS LOG: Received signal 'bar'
      JS LOG: Received signal 'bar' (handler 2)
      JS LOG: Received signal 'bonk'
      JS LOG: Received signal 'bar'
      JS LOG: Received signal 'bar' (handler 2)
      JS LOG: running test testExceptionInCallback
      JS LOG: Received signal 'bar' (throwing exception)
    JS ERROR: !!!   Exception in callback for signal: bar
    JS ERROR: !!!     message = 'Exception we are throwing on purpose'
    JS ERROR: !!!     lineNumber = '119'
    JS ERROR: !!!     fileName = '/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js'
    JS ERROR: !!!     stack = 'Error("Exception we are throwing on purpose")@:0
([object Object])@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:119
_emit("bar")@/tmp/buildd/gjs-0.5/_build/./modules/signals.js:124
testExceptionInCallback()@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:128
gjstestRun()@/tmp/buildd/gjs-0.5/_build/modules/jsUnit.js:471
@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:138
'
      JS LOG: Received signal 'bar' (handler 2)
      JS LOG: Received signal 'bar' (throwing exception)
    JS ERROR: !!!   Exception in callback for signal: bar
    JS ERROR: !!!     message = 'Exception we are throwing on purpose'
    JS ERROR: !!!     lineNumber = '119'
    JS ERROR: !!!     fileName = '/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js'
    JS ERROR: !!!     stack = 'Error("Exception we are throwing on purpose")@:0
([object Object])@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:119
_emit("bar")@/tmp/buildd/gjs-0.5/_build/./modules/signals.js:124
testExceptionInCallback()@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:133
gjstestRun()@/tmp/buildd/gjs-0.5/_build/modules/jsUnit.js:471
@/tmp/buildd/gjs-0.5/_build/test/js/testSignals.js:138
'
      JS LOG: Received signal 'bar' (handler 2)
      JS CTX: Script evaluation succeeded
      JS CTX: Script returned integer code 0
   JS MEMORY: Memory report: before destroying context
   JS MEMORY:   1 objects currently alive
   JS MEMORY:            boxed = 0
   JS MEMORY:          closure = 0
   JS MEMORY:         database = 0
   JS MEMORY:     dbus_exports = 0
   JS MEMORY:         function = 0
   JS MEMORY:         importer = 1
   JS MEMORY:               ns = 0
   JS MEMORY:           object = 0
   JS MEMORY:            param = 0
   JS MEMORY:             repo = 0
   JS MEMORY:        resultset = 0
   JS MEMORY:         weakhash = 0
      JS CTX: Destroying JS context
      JS CTX: Clearing call context
      JS CTX: Call context cleared
      JS CTX: Clearing load context
      JS CTX: Destroying JS context (load context)
      JS CTX: Load context cleared
      JS CTX: Destroying JS runtime
      JS CTX: Destroying any remaining dataset items on runtime
   JS MEMORY: Memory report: after destroying context
   JS MEMORY:   1 objects currently alive
   JS MEMORY:            boxed = 0
   JS MEMORY:          closure = 0
   JS MEMORY:         database = 0
   JS MEMORY:     dbus_exports = 0
   JS MEMORY:         function = 0
   JS MEMORY:         importer = 1
   JS MEMORY:               ns = 0
   JS MEMORY:           object = 0
   JS MEMORY:            param = 0
   JS MEMORY:             repo = 0
   JS MEMORY:        resultset = 0
   JS MEMORY:         weakhash = 0

The failure doesn't occur with GJS_DISABLE_JIT.

I ran the test through GDB, and I do see a call to js_GC with GC_LAST_CONTEXT after calling JS_DestroyContext on the last context. However, I never see a call to importer_finalize or JS_FinalizeStub (which I expected to see when finalizing the global object). I see calls to importer_finalize and JS_FinalizeStub on amd64, where it seems to be working ok.

I'll attach a minimal reproducer which I can use to trigger the issue on i386, which is basically just a very stripped down gjstestRun. Running the script with gjs-console triggers the issue