It seems the categories are underutilized. (Just "GCC Error" and "GCC Warning"). Is it possible to have finer grain bins based on the actual warning text, stripping out warning instance variability?.

E.g.(not sure if it is worth prefixing with "GCC Warning" or not)
GCC Warning - unused variable
GCC Warning - comparison is always false due to limited range of data type
GCC Warning - incompatible implicit declaration of built-in function
GCC Warning - defined but not used
GCC Warning - implicit declaration of function
GCC Warning - may be used uninitialized in this function
GCC Warning - return type of 'main' is not 'int'
GCC Warning - return type defaults to 'int'
GCC Warning - format expects type
GCC Warning - pointer targets in differ in signedness

and for anything that didn't match something more specific:

GCC Warning - other

This would allow better summarization of issues in assessing state of the code.

This stratagem may apply to all GCC versions of compilers?