complibs/cloog: fix linking with libm

In Ubuntu 11.04 and 11.10, the default options for ld have changed.
--no-copy-dt-needed-entries and --as-needed are now enabled by default, which
causes errors like:

[EXTRA] Checking CLooG/ppl
[DEBUG] ==> Executing: 'make' '-j3' '-s' 'check'
[ALL ] Making check in .
[ALL ] config.status: creating include/cloog/cloog-config.h
[ALL ] config.status: include/cloog/cloog-config.h is unchanged
[ALL ] libtool: link: i686-build_pc-linux-gnu-gcc -Wall -fomit-frame-pointer
-pipe -o cloog cloog.o -L/<snip>/build/static/lib ./.libs/libcloog.a -lm
/<snip>/build/static/lib/libppl_c.a /<snip>/build/static/lib/libpwl.a
/<snip>/build/static/lib/libppl.a /<snip>/build/static/lib/libgmpxx.a
/<snip>/build/static/lib/libgmp.a -lstdc++
[ALL ] /usr/bin/ld: /<snip>/build/static/lib/libppl.a(MIP_Problem.o):
undefined reference to symbol 'sqrt@@GLIBC_2.0'
[ALL ] /usr/bin/ld: note: 'sqrt@@GLIBC_2.0' is defined in DSO
/usr/lib/gcc/i686-linux-gnu/4.6.1/../../../i386-linux-gnu/libm.so so try adding
it to the linker command line
[ALL ] /usr/lib/gcc/i686-linux-gnu/4.6.1/../../../i386-linux-gnu/libm.so:
could not read symbols: Invalid operation
[ALL ] collect2: ld returned 1 exit status
[ERROR] make[2]: *** [cloog] Error 1
[ERROR] make[1]: *** [check-recursive] Error 1

See:
https://wiki.ubuntu.com/NattyNarwhal/ToolchainTransition

This patch fixes these errors by placing '-lm' at the right place on the command
line as libppl requires libm when linking cloog.

Signed-off-by: "Benoît Thébaudeau" <benoit.thebaudeau@advansee.com>

Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org> wrote:

I tried to use crosstool-ng to generate a toolchain for Linux on big

endian arm with recent versions of gcc, glibc, etc... but had a few

problems.

It appears that the gcc patch (for gcc 4.2.x)

for big-endian arm (240-arm-bigendian.patch) lacks the change attached

to this mail as 240-arm-bigendian2.patch.

--- gcc-4.2.4/gcc/config/arm/bpabi.h~	2007-09-01 17:28:30.000000000 +0200

+++ gcc-4.2.4/gcc/config/arm/bpabi.h	2009-01-05 19:19:10.000000000 +0100

@@ -32,9 +32,19 @@

 #undef FPUTYPE_DEFAULT

 #define FPUTYPE_DEFAULT FPUTYPE_VFP

+/*

+ * 'config.gcc' defines TARGET_BIG_ENDIAN_DEFAULT as 1 for arm*b-*

+ * (big endian) configurations.

+ */

+#if TARGET_BIG_ENDIAN_DEFAULT

+#define TARGET_ENDIAN_DEFAULT MASK_BIG_END

+#else

+#define TARGET_ENDIAN_DEFAULT 0

+#endif

+

 /* EABI targets should enable interworking by default.  */

 #undef TARGET_DEFAULT

-#define TARGET_DEFAULT MASK_INTERWORK

+#define TARGET_DEFAULT (MASK_INTERWORK | TARGET_ENDIAN_DEFAULT)

 /* The ARM BPABI functions return a boolean; they use no special

    calling convention.  */