Reproduce by entering some #error's into any project and attempting to compile. This was the test code I used:
#error "This is error 1."
#error "This is error 2."
#error "This is error 3."
#error "This is error 4."
#error "This is error 5."
#warn "This is warning 1."
#warn "This is warning 2."
#warn "This is warning 3."
#warn "This is warning 4."
#warn "This is warning 5."
Expected Results:
5 errors, 5 warnings.
Actual Results:
0 errors, 5 warnings.
Present in both dreammaker and the command-line dm.exe. Have observed this for a while now (probably months).
The #error and #warn behaviors have other issues, but this is probably the only one fixable without substantially rewriting the preprocessor.
Edit: Also note that other errors also don't seem to properly increment the count. This includes "unexpected token", and probably more.