gcc: add patch to support musl on ppc

Tested with a boot in Qemu (g3beige).

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/gcc/5.4.0/911-ppc-musl-support.patch

@@ -0,0 +1,75 @@
+Add support for musl on ppc32
+
+Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
+
+diff -Nur gcc-5.4.0.orig/gcc/config/rs6000/sysv4.h gcc-5.4.0/gcc/config/rs6000/sysv4.h
+--- gcc-5.4.0.orig/gcc/config/rs6000/sysv4.h	2015-09-24 15:46:45.000000000 +0200
++++ gcc-5.4.0/gcc/config/rs6000/sysv4.h	2016-11-27 13:12:33.226953738 +0100
+@@ -537,6 +537,9 @@
+ #ifndef CC1_SECURE_PLT_DEFAULT_SPEC
+ #define CC1_SECURE_PLT_DEFAULT_SPEC ""
+ #endif
++#ifndef LINK_SECURE_PLT_DEFAULT_SPEC
++#define LINK_SECURE_PLT_DEFAULT_SPEC ""
++#endif
+ 
+ /* Pass -G xxx to the compiler.  */
+ #undef CC1_SPEC
+@@ -757,17 +760,23 @@
+ 
+ #define LINK_START_LINUX_SPEC ""
+ 
++#define MUSL_DYNAMIC_LINKER_E ENDIAN_SELECT("","le","")
++
+ #define GLIBC_DYNAMIC_LINKER "/lib/ld.so.1"
+ #define UCLIBC_DYNAMIC_LINKER "/lib/ld-uClibc.so.0"
++#define MUSL_DYNAMIC_LINKER \
++  "/lib/ld-musl-powerpc" MUSL_DYNAMIC_LINKER_E "%{msoft-float:-sf}.so.1"
+ #if DEFAULT_LIBC == LIBC_UCLIBC
+-#define CHOOSE_DYNAMIC_LINKER(G, U) "%{mglibc:" G ";:" U "}"
++#define CHOOSE_DYNAMIC_LINKER(G, U, M) "%{mglibc:" G ";:%{mmusl:" M ";:" U "}}"
++#elif DEFAULT_LIBC == LIBC_MUSL
++#define CHOOSE_DYNAMIC_LINKER(G, U, M) "%{mglibc:" G ";:%{muclibc:" U ";:" M "}}"
+ #elif !defined (DEFAULT_LIBC) || DEFAULT_LIBC == LIBC_GLIBC
+-#define CHOOSE_DYNAMIC_LINKER(G, U) "%{muclibc:" U ";:" G "}"
++#define CHOOSE_DYNAMIC_LINKER(G, U, M) "%{muclibc:" U ";:%{mmusl:" M ";:" G "}}"
+ #else
+ #error "Unsupported DEFAULT_LIBC"
+ #endif
+ #define GNU_USER_DYNAMIC_LINKER \
+-  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER)
++  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER, MUSL_DYNAMIC_LINKER)
+ 
+ #define LINK_OS_LINUX_SPEC "-m elf32ppclinux %{!shared: %{!static: \
+   %{rdynamic:-export-dynamic} \
+@@ -889,6 +898,7 @@
+   { "link_os_openbsd",		LINK_OS_OPENBSD_SPEC },			\
+   { "link_os_default",		LINK_OS_DEFAULT_SPEC },			\
+   { "cc1_secure_plt_default",	CC1_SECURE_PLT_DEFAULT_SPEC },		\
++  { "link_secure_plt_default",	LINK_SECURE_PLT_DEFAULT_SPEC },		\
+   { "cpp_os_ads",		CPP_OS_ADS_SPEC },			\
+   { "cpp_os_yellowknife",	CPP_OS_YELLOWKNIFE_SPEC },		\
+   { "cpp_os_mvme",		CPP_OS_MVME_SPEC },			\
+diff -Nur gcc-5.4.0.orig/gcc/config/rs6000/sysv4le.h gcc-5.4.0/gcc/config/rs6000/sysv4le.h
+--- gcc-5.4.0.orig/gcc/config/rs6000/sysv4le.h	2015-09-24 15:46:45.000000000 +0200
++++ gcc-5.4.0/gcc/config/rs6000/sysv4le.h	2016-11-27 13:12:33.226953738 +0100
+@@ -31,3 +31,5 @@
+ /* Little-endian PowerPC64 Linux uses the ELF v2 ABI by default.  */
+ #define LINUX64_DEFAULT_ABI_ELFv2
+ 
++#undef MUSL_DYNAMIC_LINKER_E
++#define MUSL_DYNAMIC_LINKER_E ENDIAN_SELECT("","le","le")
+diff -Nur gcc-5.4.0.orig/gcc/config.gcc gcc-5.4.0/gcc/config.gcc
+--- gcc-5.4.0.orig/gcc/config.gcc	2015-09-10 16:17:53.000000000 +0200
++++ gcc-5.4.0/gcc/config.gcc	2016-11-27 13:14:17.149638148 +0100
+@@ -2413,6 +2413,10 @@
+ 	    powerpc*-*-linux*paired*)
+ 		tm_file="${tm_file} rs6000/750cl.h" ;;
+ 	esac
++	case ${target} in
++	    powerpc*-*-linux*-musl*)
++		enable_secureplt=yes ;;
++	esac
+ 	if test x${enable_secureplt} = xyes; then
+ 		tm_file="rs6000/secureplt.h ${tm_file}"
+ 	fi