495314 - TM:uintN < 0 in ReconstructImacroPCStack

Status: RESOLVED DUPLICATE of bug 502241

(Core :: JavaScript Engine, defect)

Description

[Igor Bukanov]

ReconstructImacroPCStack contains:

    uintN pcdepth = ReconstructPCStack(cx, script, fp->imacpc, pcstack);
    if (pcdepth < 0)
        return pcdepth;
 
That uintN should be intN here.

Comment 1

[Igor Bukanov]

There is more of this type of code which GCC 4.2 complains about in addition to the above fragment:

/home/igor/m/tm/js/src/jsopcode.cpp: In function 'intN SimulateImacroCFG(JSContext*, JSScript*, uintN, jsbytecode*, jsbytecode*, jsbytecode**)':
/home/igor/m/tm/js/src/jsopcode.cpp:5365: warning: comparison of unsigned expression >= 0 is always true
/home/igor/m/tm/js/src/jsopcode.cpp:5381: warning: comparison of unsigned expression >= 0 is always true
/home/igor/m/tm/js/src/jsopcode.cpp:5381: warning: comparison of unsigned expression >= 0 is always true
/

The line are:

  5363             uintN tmp_pcdepth = SimulateImacroCFG(... 
  5365             if (tmp_pcdepth >= 0) {


  5381     LOCAL_ASSERT(pcdepth >= 0);


In both cases it is caused by using an unsigned type in place of signed one.

Comment 2

[Graydon Hoare :graydon]

It appears that this was fixed in bug 502241. Aside from the new redundant cast to uintN and back to intN in the early return of ReconstructImacroPCStack. Close?