gcc5: Fix build on NIOS2

The gcc 5.3 does not build on NIOS2 due to a missing MUSL_DYNAMIC_LINKER
definition in it's config file. Add the definition to fix the build issue.
The output produced during the failing build is as follows:

g++    -isystem/b/tmp/sysroots/x86_64-linux/usr/include -O2 -pipe -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE  -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings   -DHAVE_CONFIG_H -static-libstdc++ -static-libgcc -L/b/tmp/sysroots/x86_64-linux/usr/lib -L/b/tmp/sysroots/x86_64-linux/lib -Wl,-rpath-link,/b/tmp/sysroots/x86_64-linux/usr/lib -Wl,-rpath-link,/b/tmp/sysroots/x86_64-linux/lib -Wl,-rpath,/b/tmp/sysroots/x86_64-linux/usr/lib -Wl,-rpath,/b/tmp/sysroots/x86_64-linux/lib -Wl,-O1 gcc-ar.o -o gcc-ar \
        file-find.o libcommon.a ../libcpp/libcpp.a   ../libbacktrace/.libs/libbacktrace.a ../libiberty/libiberty.a ../libdecnumber/libdecnumber.a
In file included from ./tm.h:27:0,
                 from /b/tmp/work-shared/gcc-5.3.0-r0/gcc-5.3.0/gcc/gcc.c:34:
./config/linux.h:92:28: error: expected ',' or ';' before 'MUSL_DYNAMIC_LINKER'
     BIONIC_DYNAMIC_LINKER, MUSL_DYNAMIC_LINKER)
                            ^
./config/linux.h:59:60: note: in definition of macro 'CHOOSE_DYNAMIC_LINKER1'
   "%{" LIBC2 ":" LD2 ";:%{" LIBC3 ":" LD3 ";:%{" LIBC4 ":" LD4 ";:" LD1 "}}}"
                                                            ^
./config/linux.h:91:3: note: in expansion of macro 'CHOOSE_DYNAMIC_LINKER'
   CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER, \
   ^
./config/nios2/linux.h:40:25: note: in expansion of macro 'GNU_USER_DYNAMIC_LINKER'
       -dynamic-linker " GNU_USER_DYNAMIC_LINKER "} \
                         ^
/b/tmp/work-shared/gcc-5.3.0-r0/gcc-5.3.0/gcc/gcc.c:884:32: note: in expansion of macro 'LINK_SPEC'
 static const char *link_spec = LINK_SPEC;
                                ^
<command-line>:0:27: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]
/b/tmp/work-shared/gcc-5.3.0-r0/gcc-5.3.0/gcc/gcc.c:1295:48: note: in expansion of macro 'STANDARD_STARTFILE_PREFIX'
 static char *const standard_startfile_prefix = STANDARD_STARTFILE_PREFIX;

(From OE-Core rev: c8ec931b07c08e27027b38313e6776875db12acb)

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Khem Raj <raj.khem@gmail.com>
Cc: Ross Burton <ross.burton@intel.com>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 12 insertions, 0 deletions

diff --git a/meta/recipes-devtools/gcc/gcc-5.3.inc b/meta/recipes-devtools/gcc/gcc-5.3.inc
index 3ce089325f..80999c1111 100644
--- a/meta/recipes-devtools/gcc/gcc-5.3.inc
+++ b/meta/recipes-devtools/gcc/gcc-5.3.inc
@@ -76,6 +76,7 @@ SRC_URI = "\
            file://0044-Adding-mmusl-as-a-musl-libc-specifier-and-the-necess.patch \
            file://0045-Support-for-arm-linux-musl.patch \
            file://0046-Get-rid-of-ever-broken-fixincludes-on-musl.patch \
+           file://0047-Fix-nios2-musl-build.patch \
           "
 
 BACKPORTS = ""
diff --git a/meta/recipes-devtools/gcc/gcc-5.3/0047-Fix-nios2-musl-build.patch b/meta/recipes-devtools/gcc/gcc-5.3/0047-Fix-nios2-musl-build.patch
new file mode 100644
index 0000000000..44cea8485f
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc-5.3/0047-Fix-nios2-musl-build.patch
@@ -0,0 +1,11 @@
+diff -Naru gcc-5.3.0.orig/gcc/config/nios2/linux.h gcc-5.3.0/gcc/config/nios2/linux.h
+--- gcc-5.3.0.orig/gcc/config/nios2/linux.h     2015-05-28 16:08:37.000000000 +0200
++++ gcc-5.3.0/gcc/config/nios2/linux.h  2016-01-04 02:42:46.878844806 +0100
+@@ -30,6 +30,7 @@
+ #define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
+ 
+ #define GLIBC_DYNAMIC_LINKER "/lib/ld-linux-nios2.so.1"
++#define MUSL_DYNAMIC_LINKER  "/lib/ld-musl-nios2.so.1"
+ 
+ #undef LINK_SPEC
+ #define LINK_SPEC LINK_SPEC_ENDIAN \