Re: Bug: setjmp multilib appears broken

[Jeff Johnston <jjohnstn at redhat dot com>]

The move to the new configure/automake uses $(CCASCOMPILE) for compiling 
.S files into .o files.  This ends up being the same gcc compiler used 
for C files.  However, CCASCOMPILE uses its own set of flags: e.g. 
CCASFLAGS instead of CFLAGS.

Now, config-ml.in which adds the multilib logic gets special multilib 
flags from the compiler and appends them to a set of flags to be passed 
when building a particular multilib.  It adds these flags to CFLAGS, but 
neglects to add them to CCASFLAGS.

I propose the attached patch to fix this.  Shaun, please try it out.

DJ, I cc'd you as you are listed in the MAINTAINERS file for 
config-ml.in.  Ok?

-- Jeff J.

Shaun Jackman wrote:
> The functions setjmp and longmp in the thumb libc.a are in fact
> compiled as ARM code.
>
> The linker complains when I attempt to link my program.
>
> /usr/local/lib/gcc/arm-elf/4.1.0/../../../../arm-elf/bin/ld:
> /usr/local/lib/gcc/arm-elf/4.1.0/../../../../arm-elf/lib/thumb/libg.a(lib_a-setjmp.o)(longjmp): 
>
> warning: interworking not enabled.
>  first occurrence: proc.o: thumb call to arm
> proc.o: In function `kexit':../../kernel/proc.c:55: warning: internal
> error: dangerous error
>
> $ arm-elf-objdump -rS 
> ./arm-elf/thumb/newlib/libc/machine/arm/lib_a-setjmp.o
>
> ./arm-elf/thumb/newlib/libc/machine/arm/lib_a-setjmp.o:     file
> format elf32-littlearm
>
> Disassembly of section .text:
>
> 00000000 <setjmp>:
>   0:   e8a07ff0        stmia   r0!, {r4, r5, r6, r7, r8, r9, sl, fp,
> ip, sp, lr}
>   4:   e3a00000        mov     r0, #0  ; 0x0
>   8:   e31e0001        tst     lr, #1  ; 0x1
>   c:   01a0f00e        moveq   pc, lr
>  10:   e12fff1e        bx      lr
>
> 00000014 <longjmp>:
>  14:   e8b07ff0        ldmia   r0!, {r4, r5, r6, r7, r8, r9, sl, fp,
> ip, sp, lr}
>  18:   e1b00001        movs    r0, r1
>  1c:   03a00001        moveq   r0, #1  ; 0x1
>  20:   e31e0001        tst     lr, #1  ; 0x1
>  24:   01a0f00e        moveq   pc, lr
>  28:   e12fff1e        bx      lr
>
> Here are the relevant lines from the compilation:
>
> make[9]: Entering directory
> `/home/sjackman/src/toolchain/src/_build/arm-elf/thumb/newlib/libc/machine/arm' 
>
> arm-elf-gcc -B/home/sjackman/src/toolchain/src/_build/arm-elf/newlib/
> -isystem 
> /home/sjackman/src/toolchain/src/_build/arm-elf/newlib/targ-include
> -isystem /home/sjackman/src/toolchain/src/newlib/libc/include -O2
> -D__NO_SYSCALLS__ -DNO_FLOATING_POINT -DHAVE_FCNTL -DHAVE_GETTIMEOFDAY
> -DHAVE_NANOSLEEP -fno-builtin    -c -o lib_a-setjmp.o `test -f
> 'setjmp.S' || echo
> '../../../../../../../newlib/libc/machine/arm/'`setjmp.S
> rm -f lib.a
> arm-elf-ar cru lib.a lib_a-setjmp.o lib_a-access.o
> arm-elf-ranlib lib.a
> make[9]: Leaving directory
> `/home/sjackman/src/toolchain/src/_build/arm-elf/thumb/newlib/libc/machine/arm' 
>
>
> It looks as though the option -mthumb has been omitted.
>
> Cheers,
> Shaun

Index: config-ml.in
===================================================================
RCS file: /cvs/src/src/config-ml.in,v
retrieving revision 1.17
diff -u -p -r1.17 config-ml.in
--- config-ml.in	14 Jul 2005 01:24:56 -0000	1.17
+++ config-ml.in	2 Jun 2006 18:46:24 -0000
@@ -546,6 +546,7 @@ multi-do:
 		flags=`echo $$i | sed -e 's/^[^;]*;//' -e 's/@/ -/g'`; \
 		if (cd ../$${dir}/$${lib}; $(MAKE) $(FLAGS_TO_PASS) \
 				CFLAGS="$(CFLAGS) $${flags}" \
+				CCASFLAGS="$(CCASFLAGS) $${flags}" \
 				FCFLAGS="$(FCFLAGS) $${flags}" \
 				FFLAGS="$(FFLAGS) $${flags}" \
 				ADAFLAGS="$(ADAFLAGS) $${flags}" \