Properly set linker flags

[Andreas Jaeger <aj@suse.de>]

Compiling grub2 with gcc 4.7
gcc -Os -Wall -W -Wshadow -Wpointer-arith -Wmissing-prototypes -Wundef 
-Wstrict-prototypes -g -fno-dwarf2-cfi-asm -m64 -mcmodel=large 
-mno-red-zone -fno-stack-protector -mno-stack-arg-probe -Werror 
-Wno-trampolines -DUSE_ASCII_FAILBACK=1 -DHAVE_UNIFONT_WIDTHSPEC=1 
    -ffreestanding   -static -m64 -Wl,--build-id=none  -melf_x86_64 
-nostdlib -Wl,-N,-r,-d   -o trig.module  trig_module-trigtables.o
gcc -DHAVE_CONFIG_H -I. -I..  -Wall -W -I../include -I../include 
-DGRUB_MACHINE_EFI=1 -DGRUB_MACHINE=X86_64_EFI -nostdinc -isystem 
/usr/lib64/gcc/x86_64-suse-linux/4.7/include 
-DGRUB_FILE=\"bus/usb/usbtrans.c\" -I. -I. -I.. -I.. -I../include 
-I../include     -Os -Wall -W -Wshadow -Wpointer-arith 
-Wmissing-prototypes -Wundef -Wstrict-prototypes -g -fno-dwarf2-cfi-asm 
-m64 -mcmodel=large -mno-red-zone -fno-stack-protector 
-mno-stack-arg-probe -Werror -Wno-trampolines -DUSE_ASCII_FAILBACK=1 
-DHAVE_UNIFONT_WIDTHSPEC=1         -ffreestanding   -c -o 
bus/usb/usb_module-usbtrans.o `test -f 'bus/usb/usbtrans.c' || echo 
'./'`bus/usb/usbtrans.c
gcc: error: unrecognized command line option '-melf_x86_64'

to pass linker flags to gcc, we should use -Wl,-melf_x86_64

Here's the obvious patch against 1.99 that should still apply to current 
head,

Andreas

Index: grub-1.99/conf/Makefile.common
===================================================================
--- grub-1.99.orig/conf/Makefile.common
+++ grub-1.99/conf/Makefile.common
@@ -11,10 +11,10 @@ if COND_i386_pc
    CFLAGS_PLATFORM += -mrtd -mregparm=3
  endif
  if COND_i386_efi
-  LDFLAGS_PLATFORM = -melf_i386
+  LDFLAGS_PLATFORM = -Wl,-melf_i386
  endif
  if COND_x86_64_efi
-  LDFLAGS_PLATFORM = -melf_x86_64
+  LDFLAGS_PLATFORM = -Wl,-melf_x86_64
  endif
  if COND_i386_qemu
    CFLAGS_PLATFORM += -mrtd -mregparm=3

-- 
  Andreas Jaeger aj@{suse.com,opensuse.org} Twitter/Identica: jaegerandi
   SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
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