AX_REQUIRE_DEFINED is a simple helper for making sure other macros have been defined and thus are available for use. This avoids random issues where a macro isn’t expanded. Instead the configure script emits a non-fatal:
./configure: line 1673: AX_CFLAGS_WARN_ALL: command not found
It’s like AC_REQUIRE except it doesn’t expand the required macro.
Here’s an example:
Download the latest version of ax_require_defined.m4 or browse the macro’s revision history.
Copyright © 2014 Mike Frysinger firstname.lastname@example.org
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