cbuffTest MPLAB Project doesn't build with PICC18 v9.80 toolsuite

[codinghead]

PICC18 toolsuite can't build the cbuffTest project.

p1.exe also crashes during build.

Failure message:

Build C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test\cbuffTest_PIC18_PICC-18
for device 18F4520
Using driver C:\Program Files\HI-TECH Software\PICC-18\9.80\bin\picc18.exe

Make: The target "C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test\cbuff.p1" is
out of date.
Executing: "C:\Program Files\HI-TECH Software\PICC-18\9.80\bin\picc18.exe"
--pass1 "C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test....\cbuff_module\cbuff.c"
-q --chip=18F4520 -P
--runtime=default,+clear,+init,-keep,-download,+stackwarn,-config,+clib,+plib
--opt=default,+asm,-debug,-speed,+space,9 --warn=0 -D__DEBUG=1 -Blarge
--double=24 --float=24 --cp=16 --addrqual=ignore -g --asmlist
"--errformat=Error [%n] %f; %l.%c %s" "--msgformat=Advisory[%n] %s"
"--warnformat=Warning [%n] %f; %l.%c %s"
Make: The target "C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test\circBufferTest.p1"
is out of date.
Executing: "C:\Program Files\HI-TECH Software\PICC-18\9.80\bin\picc18.exe"
--pass1 "C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test..\circBufferTest.c"
-q --chip=18F4520 -P
--runtime=default,+clear,+init,-keep,-download,+stackwarn,-config,+clib,+plib
--opt=default,+asm,-debug,-speed,+space,9 --warn=0 -D__DEBUG=1 -Blarge
--double=24 --float=24 --cp=16 --addrqual=ignore -g --asmlist
"--errformat=Error [%n] %f; %l.%c %s" "--msgformat=Advisory[%n] %s"
"--warnformat=Warning [%n] %f; %l.%c %s"
Warning [359] C:\Documents and Settings\stuart.cording\My
Documents\sw-dev\cbuff-module\cbuffTest\cbuff_PIC18_PICC-18_test..\circBufferTest.c;
442.30 illegal conversion between pointer types
pointer to struct
********** Build failed! **********