pmc2c silently ignores bad code

[coke]

Originally reported in  RT

Summary of that ticket (quoting allison)

Pmc2c is just a series of regular expressions. It looks for specific 
patterns, and if it finds them, builds relevant C code out of them.

It has no ability to check for arbitrary syntax that *doesn't* match a 
pattern. It's a preprocessor (macro substitution), not a language parser.

What could be done is have it dump anything leftover after the 
extraction into the resulting C file. Then you'd get a C error on 
compilation.