On Sun, May 3, 2009 at 1:03 AM, Zach Welch <z...@superlucidity.net> wrote: > On Sun, 2009-05-03 at 00:40 +0200, Michael Schwingen wrote: >> Zach Welch wrote: >> > If the header is required, the configure step should fail when it is not >> > found in the system. The rule is to fail as early as possible. >> > >> > Which headers? >> > >> Not system headers - I was thinking about in-project headers (either >> user-edited, config.h or similar) that define some kind of >> INCLUDE_FEATURE_XXX switch. When multiple source files depend on that >> switch, forgetting to include it in one of them can get "interesting" >> results when using #ifdef. > > These type of features can be handled by --enable-feature-xxx options. > > The autoconf 2.63 info pages are great documentation. Section 4.9.1 > explains the config.h header fairly well, while Section 6.2.1 explains > the differences between #if and #ifdef: > > """ > Both `#if HAVE_STDBOOL_H' and `#ifdef HAVE_STDBOOL_H' will work with > any standard C compiler. Some developers prefer `#if' because it is > easier to read, while others prefer `#ifdef' because it avoids > diagnostics with picky compilers like GCC with the `-Wundef' option. > """ > > As you can imagine, I favor #ifdef for this reason.
I can't see your point. The idea of -Wundef is to warn you if you forgot to include a configuration file that defines variables that you use in your source code. And you say you favor #ifdef over #if because with #ifdef you will not be warned about your mistake ?! Michael _______________________________________________ Openocd-development mailing list Openocd-development@lists.berlios.de https://lists.berlios.de/mailman/listinfo/openocd-development
