diff options
| author | Tor Lillqvist <tml@iki.fi> | 2013-01-31 20:44:25 +0200 |
|---|---|---|
| committer | Tor Lillqvist <tml@iki.fi> | 2013-01-31 21:43:59 +0200 |
| commit | c5b1441ede3c58f1fe92372cbb48864f9d4df6ec (patch) | |
| tree | c86b771e67121fe3ff1711f403bd633c02e93ec4 /config_host/README | |
| parent | 0e63a97066a817f3d01b40d99e3e1ed831ae3598 (diff) | |
Use separate config_*.h files for BUILD and HOST when cross-compiling
We have only been lucky so far that there hasn't been any compilation errors
caused by using the HOST platform config_*.h files also for the BUILD
platform. But as more and more information found out during configury is
stored in config_*.h files, sooner or later it will be a problem.
Move config/* to config_host/*. When not cross-compiling, the config_*.h files
in config_host expanded from config_*.h.in are all there is. When
cross-compiling, the generated config_*.h files for the BUILD platform are
put into a config_build folder.
Then use config_build when building the cross_toolset and config_host
otherwise.
Change-Id: I3c28cc83866bffd696b45d00dfb68e00bc2ae538
Diffstat (limited to 'config_host/README')
| -rw-r--r-- | config_host/README | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/config_host/README b/config_host/README new file mode 100644 index 000000000000..fd58b64045bb --- /dev/null +++ b/config_host/README @@ -0,0 +1,24 @@ +These are configuration files for various features as detected by configure. + +Include only those files you need (in order to reduce rebuilds when a setting changes). + +Settings here are only C/C++ #define directives, so they apply only to C/C++ source, +not to Makefiles. + + + +Adding a new setting: +===================== + +- do AC_DEFINE(HAVE_FOO) in configure.ac when a setting should be set +- choose the proper config/config_xxx.h file to use + - if it is a global setting (such as availability of a compiler feature), + use config/config_global.h + - otherwise check if there is a matching config/config_hxx.h file + - if none matches, add a new one: + - add config/config_xxx.h.in here, with just #ifndef include guard + - add AC_CONFIG_HEADERS([config/config_xxx.h]) next to the others + in configure.ac + - add config_hxx.h to config/.gitignore +- add #undef HAVE_FOO to the config/config_hxx.h , possibly with a comment +- add #include <config_xxx.h> before any #ifdef HAVE_XXX in a source file |