[PATCH] Use linker script to remove unnecessary sections

[Bean]

Hi,

This patch use customized linker script to build *.img and *.mod
files, it should remove unnecessary sections created by the compiler.


2007-12-14  Bean  <address@hidden>

        * conf/i386-pc.rmk (COMMON_LDFLAGS): Use ldscript to link.

        * aclocal.m4 (grub_PROG_OBJCOPY_ABSOLUTE): Test ldscript.

        * configure.ac : Remove the '--build-id=none' flag.

        * ldscript : New file.


Index: conf/i386-pc.rmk
===================================================================
RCS file: /sources/grub/grub2/conf/i386-pc.rmk,v
retrieving revision 1.94
diff -u -p -r1.94 i386-pc.rmk
--- conf/i386-pc.rmk    18 Nov 2007 06:41:45 -0000      1.94
+++ conf/i386-pc.rmk    14 Dec 2007 11:51:13 -0000
@@ -2,10 +2,10 @@

 COMMON_ASFLAGS = -nostdinc -fno-builtin -m32
 COMMON_CFLAGS = -fno-builtin -mrtd -mregparm=3 -m32
-COMMON_LDFLAGS = -m32 -nostdlib
+COMMON_LDFLAGS = -m32 -nostdlib -T "${srcdir}/ldscript"

 # Images.
 pkgdata_IMAGES = boot.img diskboot.img kernel.img pxeboot.img
Index: aclocal.m4
===================================================================
RCS file: /sources/grub/grub2/aclocal.m4,v
retrieving revision 1.7
diff -u -p -r1.7 aclocal.m4
--- aclocal.m4  25 Nov 2007 02:01:30 -0000      1.7
+++ aclocal.m4  14 Dec 2007 11:51:14 -0000
@@ -57,7 +57,7 @@ else
 fi
 grub_cv_prog_objcopy_absolute=yes
 for link_addr in 2000 8000 7C00; do
-  if AC_TRY_COMMAND([${CC-cc} ${CFLAGS} ${LDFLAGS} -nostdlib -Wl,-N
-Wl,-Ttext -Wl,$link_addr conftest.o -o conftest.exec]); then :
+  if AC_TRY_COMMAND([${CC-cc} ${CFLAGS} -nostdlib -Wl,-N -Wl,-T
"-Wl,${srcdir}/ldscript" -Wl,-Ttext -Wl,$link_addr conftest.o -o
conftest.exec]); then :
   else
     AC_MSG_ERROR([${CC-cc} cannot link at address $link_addr])
   fi
Index: configure.ac
===================================================================
RCS file: /sources/grub/grub2/configure.ac,v
retrieving revision 1.40
diff -u -p -r1.40 configure.ac
--- configure.ac        25 Nov 2007 02:01:30 -0000      1.40
+++ configure.ac        14 Dec 2007 11:51:14 -0000
@@ -229,16 +229,6 @@ if test "x$target_m32" = x1; then
   TARGET_LDFLAGS="$TARGET_LDFLAGS -m32"
 fi

-AC_MSG_CHECKING([whether the linker accepts `--build-id=none'])
-save_LDFLAGS="$LDFLAGS"
-LDFLAGS="$LDFLAGS -Wl,--build-id=none"
-AC_TRY_LINK(, , build_id_flag=yes, build_id_flag=no)
-AC_MSG_RESULT([$build_id_flag])
-LDFLAGS="$save_LDFLAGS"
-if test "x$build_id_flag" = xyes; then
-  TARGET_LDFLAGS="$TARGET_LDFLAGS -Wl,--build-id=none"
-fi
-
 #
 # Compiler features.
 #
Index: ldscript
===================================================================
RCS file: /sources/grub/grub2/ldscript,v
diff -Nu ldscript
--- /dev/null   2007-12-15 02:52:31.284046226 +0800
+++ ldscript    2007-12-14 19:37:39.546875000 +0800
@@ -0,0 +1,12 @@
+SECTIONS
+{
+  .text : { *(.text) } =0x90909090
+  .rodata : { *(.rodata .rodata.*) }
+  .data : { *(.data) }
+  PROVIDE(__bss_start = .);
+  .bss : { *(.bss) *(COMMON) }
+  PROVIDE(end = .);
+  .modname : { *(.modname) }
+  .moddep : { *(.moddep) }
+  /DISCARD/ : { *(*) }
+}

-- 
Bean