Subj : Crash in Script.exec()
To   : netscape.public.mozilla.jseng
From : celsoaguiar@hotmail.com (Celso Aguiar)
Date : Wed Dec 03 2003 04:30 pm

Could someone please help me with this problem? I'm getting a crash in
js_CheckRedeclaration when calling Script.exec() from
JS_CallfunctionName. I get the crash either if I pass in a scope
object parameter to exec (my global object) or not. The script was
obtained from frozen/thaw'ed bytecode. 'obj' in js_CheckRedeclaration
is NULL, apparently because it could not find my scopeobj, despite
passing in one.
Looking at the code in script_exec:

    fp = cx->fp;
    caller = fp->down;
    if (!scopeobj)
      scopeobj = caller->scopeChain;
    fp->thisp = caller->thisp;
    JS_ASSERT(fp->scopeChain == caller->scopeChain);
    fp->sharpArray = caller->sharpArray;
    return js_Execute(cx, scopeobj, script, fp, 0, rval);

it doesn't look like js_Execute will be able to do any good if fp
and scopeobj are non-NULL. When called from JS_CallfunctionName, 
a fp->varobj will not be available, later causing the crash. 
If I null fp (down) after entering js_Execute, and leave scopeobj
(chain) alone, all goes well.
The stack is below.
Thanks, I appreciate any help.

Celso

js_CheckRedeclaration(JSContext * cx=0x031c3d70, JSObject *
obj=0x00000000, long id=0x04445670, unsigned int attrs=0x00000005, int
* foundp=0x0012bcac)  Line 1155 + 0x19	C
js_Interpret(JSContext * cx=0x031c3d70, long * result=0x0012c2a0) 
Line 3302 + 0x4e	C
js_Execute(JSContext * cx=0x031c3d70, JSObject * chain=0x0320bef8,
JSScript * script=0x047b4840, JSStackFrame * down=0x0012c280, unsigned
int special=0x00000000, long * result=0x0012c2a0)  Line 1016 + 0xd	C
script_exec(JSContext * cx=0x031c3d70, JSObject * obj=0x044465e0,
unsigned int argc=0x00000001, long * argv=0x047c6a48, long *
rval=0x0012c2a0)  Line 250 + 0x1b	C
js_Invoke(JSContext * cx=0x031c3d70, unsigned int argc=0x00000001,
unsigned int flags=0x00000002)  Line 836 + 0x1c	C
js_InternalInvoke(JSContext * cx=0x031c3d70, JSObject *
obj=0x044465e0, long fval=0x031ca3b0, unsigned int flags=0x00000000,
unsigned int argc=0x00000001, long * argv=0x047cca68, long *
rval=0x0012c3d0)  Line 928 + 0x14	C
JS_CallFunctionName(JSContext * cx=0x031c3d70, JSObject *
obj=0x044465e0, const char * name=0x0012c4e0, unsigned int
argc=0x00000001, long * argv=0x047cca68, long * rval=0x0012c3d0)  Line
3401 + 0x1f	C
ESObjectCallEx(_s_ESObjectRec * eso=0x045d4a80, const char *
szName=0x0012c4e0, _s_ESObjectRec * esoArgs=0x045d4b60, _s_ESValRec *
esvRet=0x031f4b58, unsigned short bIgnorePermCheck=0x0001, unsigned
short bAllowUserCancel=0x0000)  Line 3539 + 0x24	C++

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