Avoid generating C trigraphs
main = print "??)"
If we compile the above with an
unregisterised ghc then some gcc versions report:
/tmp/ghc6084_0/ghc6084_0.hc:99:30: warning: trigraph ??) ignored, use -trigraphs to enable
This should make us nervous.
According to the GCC manual if we were ever to use
-std=c89 or any of the official C standard compliance modes (ie non-GNU) then we would get standard C (cpp) trigraph behavior.
We should therefore add a codeGen/should_run test to make sure that the above program does always print
"??)" and never
"]". This test only needs to be run in
It's not an immediate priority but it may trip someone up in future when porting or if we make unregisterised C code more standards compliant and start using one of the official
-std= modes. It is unlikely to hit us but if it ever did it'd be a real pain to debug.