em libmon vanished decades ago (or never existed), and also ass appears to have
a different idea of what the em opcodes are to everything else and gets
confused.
This library is for software floating point. The i80 back end has
never implemented floating point, and might not be ready for libfp.
This commit only builds libfp without using it.
I edit first/build.lua and plat/build.lua to allow `ack -c.s`, then
use FP.script to edit the assembly code. I edit FP.script so it
writes the edited assembly code to stdout, not to the input file.
Switch from custom assert() to libc assert() in mach/proto/as.
Continue to disable asserts if DEBUG == 0.
This change found a problem in the build system; comm2.y was missing
depedencies on comm0.h and comm1.h. Add the missing dependencies to
the cppfile rule. Allow the dependencies by modifying cppfile in
first/build.lua to act like cfile if t.dir is false.
Now that comm2.y gets rebuilt, I must fix the wrong prototype of
yyparse() in comm1.h.
I got unlucky as induo() in comm5.c was reading beyond the end of the
array. It found an operator "= " ('=' then space) in the garbage, so
it returned a garbage token number, and "VAR = 123" became a syntax
error. Unbreak induo() by terminating the array.
