Re: When crosscompiling, does configure really need --build?

[Akim Demaille]

| I'm using autoconf 2.53.  
| When I run configure, I override CC and the like
| in the environment to point to my cross-compiler like this:
| 
| CC=/opt/hardhat/devkit/ppc/405/bin/ppc_405-gcc
| AR=/opt/hardhat/devkit/ppc/405/bin/ppc_405-ar
| RANLIB=/opt/hardhat/devkit/ppc/405/bin/ppc_405-ranlib CFLAGS="-mcpu=403
| -D__PPC405__"  ./configure --prefix=/
| 
| Configuring without --host or --build yields the error
| "If you meant to cross compile, use `--host'."
| 
| Configuring with --host but without --build yields the warning
| "configure: WARNING: If you wanted to set the --build type, don't use
| --host.
|     If a cross compiler is detected then cross compile mode will be used."
| 
| So I configure with both --host and --build, but that's really annoying,
| as I posted originally.  I just can't win.  How do I configure for
| cross-compiling
| without warnings or errors, and without hard-coding info about the build
| machine into my build scripts?

You are supposed to run this as:

      ./configure --prefix=/ --host=ppc_405 CFLAGS="-mcpu=403 -D__PPC405__"

You are to tell the configure that you are cross-compiling.  It cannot
guess it, so it is entitled to fail.  Please, read the documentation.