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>

diff -durN gcc-3.4.6.orig/gcc/flow.c gcc-3.4.6/gcc/flow.c

--- gcc-3.4.6.orig/gcc/flow.c	2005-09-01 22:51:09.000000000 +0200

+++ gcc-3.4.6/gcc/flow.c	2007-08-15 23:00:30.000000000 +0200

@@ -1884,6 +1884,7 @@

 	  rtx set_src = SET_SRC (pc_set (BB_END (bb)));

 	  rtx cond_true = XEXP (set_src, 0);

 	  rtx reg = XEXP (cond_true, 0);

+ 	  enum rtx_code inv_cond;

 	  if (GET_CODE (reg) == SUBREG)

 	    reg = SUBREG_REG (reg);

@@ -1892,11 +1893,13 @@

 	     in the form of a comparison of a register against zero.  

 	     If the condition is more complex than that, then it is safe

 	     not to record any information.  */

-	  if (GET_CODE (reg) == REG

+ 	  inv_cond = reversed_comparison_code (cond_true, BB_END (bb));

+ 	  if (inv_cond != UNKNOWN

+	      && GET_CODE (reg) == REG

 	      && XEXP (cond_true, 1) == const0_rtx)

 	    {

 	      rtx cond_false

-		= gen_rtx_fmt_ee (reverse_condition (GET_CODE (cond_true)),

+		= gen_rtx_fmt_ee (inv_cond,

 				  GET_MODE (cond_true), XEXP (cond_true, 0),

 				  XEXP (cond_true, 1));

 	      if (GET_CODE (XEXP (set_src, 1)) == PC)