Bug 334312

Description Dave Russo 2011-01-13 14:42:00 EST

+++ This bug was initially created as a clone of Bug #333928 +++

Build Identifier: 3.20.06.81 and 3.21.00.30

The code generated for the C code below:
 
        if (module->outidx == SysMin_bufSize) {
            module->outidx = 0;
            module->wrapped = TRUE;
        }
        module->outbuf[module->outidx++] = ch;

actually executes like this:

        old_outindex = module->outidx;

        if (old_outidx == SysMin_bufSize) {
            module->outidx = 0;
            module->wrapped = TRUE;
        }
        module->outidx++;
        module->outbuf[old_outidx] = ch;

This results in a scribbling of the memory address one beyond the end of the SysMin output buffer whenever the output buffer index wraps.

Reproducible: Always