1.9 KiB
libbuild2-autoconf
GNU Autoconf emulation build system module for build2.
Specifically, this module provides an in-based rule for
processing config.h.in files. Besides the Autoconf special line flavor
(#undef), it also supports the CMake (#cmakedefine) and Meson
(#mesondefine) variants.
Similar to Autoconf, this module provides built-in support for a number of
common HAVE_* configuration options. However, the values of these options
are not discovered by dynamic probing, such as trying to compile a test
program to check if the feature is present. Instead, they are set to static
expected values based on the platform/compiler macros (see note at the
beginning of Project Configuration for rationale).
See libbuild2/autoconf/checks/ for the list of available build-in
configuration options.
Adding new configuration options.
To add a new configuration option <NAME> simply create the <NAME>.h header
file with the corresponding check and place it into
libbuild2/autoconf/checks/ (use existing checks for inspiration).
The first line in this header file must be in the form:
// <NAME>
Subsequent lines should be C-style comments or preprocessor directives that
#define or #undef <NAME> depending on whether the feature is available
(though there can be idiosyncrasies; see const.h, for example). Note that
there should be no double-quotes or backslashes except for line
continuations. For example:
// HAVE_FOO
#ifndef _WIN32
# define HAVE_FOO 1
#else
# undef HAVE_FOO /* No foo on Windows. */
#endif