Tcl package Thread source code

With a Tcl compiled with --enable-symbols , the script

package require Thread
set t1 [thread::create]
thread::send -async $t1 {lindex {}} [expr 0]

results in:

alloc: invalid block

This happens because threadSendFree obtains the length of a Tcl_Obj before the string representation for that object is generated, and a few lines later the string representation is generated.

The fix by sebres is at [98170da1657fb2dc]

Thanks Nathan (pooryorick) for finding and minimalistic fix. I've amended with more extensive fix replacing strcpy with memcpy (additionally should avoid segfault by overwrite if string representation would be possibly broken, e. g. without NTS 0-byte) and extended the test-cases to cover exactly this issue.

So fixed now in 2.8 and trunk, thus close.