Compiler for LPC2148

I'd never heard of SCARM until you posted this (you should have posted a 
link).  It is not a GNU compiler, so you are on the wrong forum. 
Moreover it is a commercial product, so you should get support from the 
vendor. http://www.spjsystems.com/support.htm

I am nor sure what you mean by "file size", but I would be very 
surprised is there were any code size limit with any compiler; the limit 
of code size is determined by your hardware.

If you rather mean the limit of source file size, then you are wrong 
thinking.  For large projects (in fact for any non-trivial project), you 
should use separate compilation and linking of a number of smaller 
modules rather than placing all your code into a single file!  Even then 
I would be surprised if there were any limit other than that imposed by 
the host Operating System - so no practical limit.

Clifford