fixed the build failure on s390x/ppc64/ppc64le against new glibc

which drops the tag struct ucontext

mono-4.8.0.520-glibc-ucontext.patch

@@ -0,0 +1,12 @@
+diff -up mono-4.8.0/mono/utils/mono-sigcontext.h.than mono-4.8.0/mono/utils/mono-sigcontext.h
+--- mono-4.8.0/mono/utils/mono-sigcontext.h.than	2017-09-20 09:47:02.344226028 -0400
++++ mono-4.8.0/mono/utils/mono-sigcontext.h	2017-09-20 09:53:16.120785421 -0400
+@@ -276,7 +276,7 @@ typedef struct ucontext {
+ #endif
+ 
+ #if defined(__linux__)
+-	typedef struct ucontext os_ucontext;
++	typedef ucontext_t os_ucontext;
+ 
+ #ifdef __mono_ppc64__
+ 	#define UCONTEXT_REG_Rn(ctx, n)   (((os_ucontext*)(ctx))->uc_mcontext.gp_regs [(n)])

mono.spec

@@ -16,7 +16,7 @@
 
 Name:           mono
 Version:        4.8.0
-Release:        11%{?dist}
+Release:        12%{?dist}
 Summary:        Cross-platform, Open Source, .NET development framework
 
 Group:          Development/Languages
@@ -34,6 +34,9 @@ Patch2:         mono-4.3.2-find-provides.patch
 Patch3:         mono-4.2-fix-winforms-trayicon.patch
 Patch4:         mono-4.6.0-patch_arm_fast_tls.patch
 Patch5:         mono-4.6.1-aarch64.patch
+# fix bz#1484151, bz#1484149 due to new glibc which
+# drops the struct ucontext
+Patch6:         mono-4.8.0.520-glibc-ucontext.patch
 
 BuildRequires:  bison
 BuildRequires:  cmake
@@ -276,6 +279,7 @@ Development file for monodoc
 %patch3 -p1
 %patch4 -p1
 %patch5 -p1
+%patch6 -p1
 
 # Add undeclared Arg
 sed -i "61a #define ARG_MAX     _POSIX_ARG_MAX" mono/io-layer/wapi_glob.h
@@ -790,6 +794,10 @@ rm -f %{buildroot}%{_libdir}/pkgconfig/cecil.pc
 %{_libdir}/pkgconfig/monodoc.pc
 
 %changelog
+* Wed Sep 20 2017 Than Ngo <than@redhat.com> - 4.8.0-12
+- fixed the build failure on s390x/ppc64/ppc64le against new glibc
+  which drops the tag struct ucontext 
+
 * Sun Aug 27 2017 Ville Skyttä <ville.skytta@iki.fi> - 4.8.0-11
 - Own dirs in %%{_monodir}/mono-configuration-crypto