Purpose
Emits macro definitions to preprocessed
output.
Emitting
macros to preprocessed output can help determine functionality available
in the compiler. The macro listing may prove useful for debugging
complex macro expansions, as well.
Syntax
.-noshowmacros---------------------.
>>- -q--+-showmacros--+------------------+-+-------------------><
| .-:---------. |
| V | |
'-=----+-all---+-+-'
+-nopre-+
'-pre---'
Parameters
- all
- Emits all macro definitions to preprocessed output. This is the
same as specifying -qshowmacros.
- pre | nopre
- pre emits only predefined macro definitions to preprocessed
output. nopre suppresses appending these definitions.
Usage
Note the following when using this
option:
- This option has no effect unless preprocessed
output is generated; for example, by using the -E or -P options.
- If a macro is defined and subsequently undefined before compilation
ends, this macro will not be included in the preprocessed output.
- Only macros defined internally by the preprocessor are considered
predefined; all other macros are considered as user-defined.