gcc: Add GCC 4.6 patches from official openwrt.git toolchain directory.

Signed-off-by: Christian Beier <dontmind@freeshell.org>

devel/gcc/patches/850-use_shared_libgcc.patch

@@ -0,0 +1,86 @@
+--- a/gcc/config/arm/linux-eabi.h
++++ b/gcc/config/arm/linux-eabi.h
+@@ -115,10 +115,6 @@
+ #define ENDFILE_SPEC \
+   LINUX_OR_ANDROID_LD (GNU_USER_TARGET_ENDFILE_SPEC, ANDROID_ENDFILE_SPEC)
+ 
+-/* Use the default LIBGCC_SPEC, not the version in linux-elf.h, as we
+-   do not use -lfloat.  */
+-#undef LIBGCC_SPEC
+-
+ /* Clear the instruction cache from `beg' to `end'.  This is
+    implemented in lib1funcs.asm, so ensure an error if this definition
+    is used.  */
+--- a/gcc/config/arm/linux-elf.h
++++ b/gcc/config/arm/linux-elf.h
+@@ -60,8 +60,6 @@
+    %{shared:-lc} \
+    %{!shared:%{profile:-lc_p}%{!profile:-lc}}"
+ 
+-#define LIBGCC_SPEC "-lgcc"
+-
+ #define GLIBC_DYNAMIC_LINKER "/lib/ld-linux.so.2"
+ 
+ #define LINUX_TARGET_LINK_SPEC  "%{h*} \
+--- a/gcc/config/linux.h
++++ b/gcc/config/linux.h
+@@ -52,6 +52,10 @@ see the files COPYING3 and COPYING.RUNTI
+ 	builtin_assert ("system=posix");			\
+     } while (0)
+ 
++#ifndef LIBGCC_SPEC
++#define LIBGCC_SPEC "%{static|static-libgcc:-lgcc}%{!static:%{!static-libgcc:-lgcc_s}}"
++#endif
++
+ /* Determine which dynamic linker to use depending on whether GLIBC or
+    uClibc or Bionic is the default C library and whether
+    -muclibc or -mglibc or -mbionic has been passed to change the default.  */
+--- a/gcc/config/rs6000/linux.h
++++ b/gcc/config/rs6000/linux.h
+@@ -88,6 +88,8 @@
+ #define USE_LD_AS_NEEDED 1
+ #endif
+ 
++#define LIBGCC_SPEC "%{!static:%{!static-libgcc:-lgcc_s}} -lgcc"
++
+ #undef  TARGET_VERSION
+ #define TARGET_VERSION fprintf (stderr, " (PowerPC GNU/Linux)");
+ 
+--- a/gcc/mkmap-symver.awk
++++ b/gcc/mkmap-symver.awk
+@@ -132,5 +132,5 @@ function output(lib) {
+   else if (inherit[lib])
+     printf("} %s;\n", inherit[lib]);
+   else
+-    printf ("\n  local:\n\t*;\n};\n");
++    printf ("\n\t*;\n};\n");
+ }
+--- a/libgcc/Makefile.in
++++ b/libgcc/Makefile.in
+@@ -269,6 +269,12 @@ ifeq ($(enable_shared),yes)
+     install-libunwind = install-libunwind
+   endif
+ 
++else
++# Not enable_shared.
++iterator = $(srcdir)/empty.mk $(patsubst %,$(srcdir)/static-object.mk,$(iter-items))
++endif
++
++
+ # For -fvisibility=hidden.  We need both a -fvisibility=hidden on
+ # the command line, and a #define to prevent libgcc2.h etc from
+ # overriding that with #pragmas.
+@@ -291,13 +297,6 @@ else
+ gen-hide-list = echo > $@
+ endif
+ 
+-else
+-# Not enable_shared.
+-iterator = $(srcdir)/empty.mk $(patsubst %,$(srcdir)/static-object.mk,$(iter-items))
+-vis_hide =
+-gen-hide-list = echo > \$@
+-endif
+-
+ ifneq ($(EXTRA_PARTS),)
+   extra-parts = libgcc-extra-parts
+   INSTALL_PARTS = $(EXTRA_PARTS)