Typecheck void type expressions in return and assignment #41
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Problem
The following 4 programs compile without error, but they obviously shouldn't.
Assigning expression with void type.
Return nothing in a non-void type function.
Return void type expression in a non-void function.
Return non-void type expression in a void type function.
Proposal
I added exactly 4 small chunks of code in
parse.c
to handle the cases above accordingly.Error reporting is also a critical part of compiler, and since the compiler prevents variable declaration with
void
type already, we should probably handle these cases too. I would even propose to separate out type-checking into a phase, but this really depends on your focus in this project.