Disable lto on ppc64le

dolfin.spec

@@ -20,6 +20,15 @@ Source2:        3083BE4C722232E28AD0828CBED06106DD22BAB3.gpg
 %global cmake_blas_flags -DBLAS_LIBRARIES=%{_libdir}/lib%{blaslib}%{blasvar}.so
 %endif
 
+# On ppc64le, lto builds fail
+# {standard input}: Assembler messages:
+# {standard input}:34337: Error: junk at end of line, first unrecognized character is `+'
+# {standard input}:34338: Error: expected comma after "operator"
+# ...
+%ifarch ppc64le
+%global _lto_cflags %nil
+%endif
+
 BuildRequires:  gcc-c++
 BuildRequires:  gnupg2
 BuildRequires:  cmake