Set the regular expression used for dependency checking.

include_regular_expression(regex_match [regex_complain])

Sets the regular expressions used in dependency checking. Only files matching regex_match will be traced as dependencies. Only files matching regex_complain will generate warnings if they cannot be found (standard header paths are not searched). The defaults are:

regex_match    = "^.*$" (match everything)
regex_complain = "^$" (match empty string only)