c--macroexpand-all

c--macroexpand-all is an alias for `macroexpand-all' in `cc-defs.el'.

(c--macroexpand-all FORM &optional ENVIRONMENT)

Return result of expanding macros at all levels in FORM.
If no macros are expanded, FORM is returned unchanged.
The second optional arg ENVIRONMENT specifies an environment of macro
definitions to shadow the loaded ones for use in file byte-compilation.