> On Fri, 2006-02-03 at 06:07 +0000, Harlan Stenn wrote: > > Ralf, > > > > How about something that would use AC_RUN_IFELSE()? > > We are talking about distinguishing different compiler > versions !!!!!!!!! No, we are talking about making decisions using, say, the version number of a tool or the output of config.guess (or something like that). > Why on earth would you want to run something conditionally, depending on > which compilers it had been compiled with? I don't know, but that doesn't mean there isn't a good reason do to it. > > There's a reason it come with ACTION-IF-CROSS-COMPILING - it means one > > CANNOT feature test so one has to make the decision beforehand and > > decide based on some other factors. > > You are talking about a package using a toolchain to require _target_ > run-time features. Right, these are occasionally required. > > But we are talking about compiler/toolchain features. The cross > compilers/toolchains *never* retrieve anything from a target at > run-time. Perhaps we had a little confusion about exactly what we were talking about. I was going off about folks who say "the only way to go is feature test - never rely on version numbers", as I have had that discussion before and it included testing based on OS type or version. In general I prefer to test. If that's "too difficult" I'll go for version numbers or the CPU-Vendor-OS string (I have something that converts the output of config.guess and some optional local poking around into something I find useful). > If the toolchains require knowledge about a target's runtime feature, > the toolchains must know about it in advance, but the > application/package using the toolchain doesn't have to. It can > compile/link check the toolchain. This is simply a degenerate case. We could certainly go back to the old days where folks said #ifdef BSD or #ifdef SYSIII. The point I was trying to make is that "feature testing is good and we cannot always do it TODAY. Sometimes we must use another way, like version numbers." H _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf