On Fri, 12 Oct 2007, Sam Ravnborg wrote: > On Fri, Oct 12, 2007 at 10:51:00AM +0200, Geert Uytterhoeven wrote: > > On Fri, 12 Oct 2007, Finn Thain wrote: > > > > If your cross-compiler is called differently than the default on in > > > > arch/*/Makefile, > > > > > > Part of the problem is that there is no compelling default. The name of > > > the cross-compiler can vary depending on the chosen executable prefix or > > > the chosen target tuple. > > > > > > Let's say I create new cross toolchains for both m68k and powerpc. I use > > > the "m68k-linux-gnu" to follow the m68k default, but let's assume powerpc > > > users prefer their default "powerpc-linux" so I follow that too. The > > > result is that I now have gcc's -B option working (or not working) in > > > suprising ways too. > > > > > > Uniformity is more helpful downstream than a different arbitrary default > > > for each architecture. Debian should patch their default into their > > > kernel > > > source packages if they've standardised on cross compiler prefixes. > > > > > > > what's the problem with calling? > > > > > > > > make ARCH=myarch CROSS_COMPILE=my-cross-compile-prefx- > > > > > > > > This has been working for +10 years on all non-ia32 platforms I ever > > > > worked on. > > > > > > But there is no problem with calling that (?). Rob's patch doesn't change > > > this. > > > > But it makes life harder for the people who use it daily. > > > > If the consensus is to not provide default cross compiler prefixes in > > arch/*/Makefile, fine for me, but IFF it's done for all architectures > > (i.e. check with the blackfin, h8300, mips, parisc, and xtensa people > > first). > > Test if the expected gcc is available and set CROSS_COMPILE > if it is present. Otherwise do not touch CROSS_COMPILE. > > m68kgcc := $(shell "test if m68k-gcc is present and echo 'y' if so") > ifeq ($(m68kgcc,y) > CROSS_COMPILE := m68k-foo > endif > > Then everyone is happy. > parisc does something similar.
64-bit parisc tests if /usr/bin/hppa64-linux-gnu- exists. If yes, it sets CROSS_COMPILE to hppa64-linux-gnu-. If no, it sets CROSS_COMPILE to hppa64-linux- 32-bit parisc unconditionally sets CROSS_COMPILE to hppa-linux-. This still breaks Rob's setup if his compiler is called differently. Anyway, here's a try to make it autodetect m68k-linux-gnu-gcc and m68k-linux-gcc. Perhaps it can be generalized in kbuild, to allow arch/*/Makefile to set a list of possible cross-compiler prefixes? Subject: m68k: Improve cross-compiler autodetection m68k: Improve cross-compiler autodetection Set CROSS_COMPILE to m68k-linux-gnu- resp. m68k-linux-, but only if such a cross compiler is found in your $PATH Signed-off-by: Geert Uytterhoeven <[EMAIL PROTECTED]> --- arch/m68k/Makefile | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/arch/m68k/Makefile +++ b/arch/m68k/Makefile @@ -22,7 +22,17 @@ LDFLAGS := -m m68kelf LDFLAGS_MODULE += -T $(srctree)/arch/m68k/kernel/module.lds ifneq ($(COMPILE_ARCH),$(ARCH)) # prefix for cross-compiling binaries - CROSS_COMPILE = m68k-linux-gnu- + m68k-linux-gnu-gcc := $(shell if [ `which m68k-linux-gnu-gcc` ]; then \ + echo y; fi) + ifeq ($(m68k-linux-gnu-gcc),y) + CROSS_COMPILE := m68k-linux-gnu- + else + m68k-linux-gcc := $(shell if [ `which m68k-linux-gcc` ]; then \ + echo y; fi) + ifeq ($(m68k-linux-gcc),y) + CROSS_COMPILE := m68k-linux- + endif + endif endif ifdef CONFIG_SUN3 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [EMAIL PROTECTED] In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds - To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html