Index: libgcc/config.host
--- libgcc/config.host.orig
+++ libgcc/config.host
@@ -346,6 +346,11 @@ aarch64*-*-freebsd*)
 	tmake_file="${tmake_file} ${cpu_type}/t-softfp t-softfp t-crtfm"
 	md_unwind_header=aarch64/freebsd-unwind.h
 	;;
+aarch64-*-openbsd*)
+	tmake_file="${tmake_file} ${cpu_type}/t-aarch64"
+	tmake_file="${tmake_file} ${cpu_type}/t-softfp t-softfp t-crtfm"
+	md_unwind_header=aarch64/aarch64-unwind.h
+	;;
 aarch64*-*-fuchsia*)
 	tmake_file="${tmake_file} ${cpu_type}/t-aarch64"
 	tmake_file="${tmake_file} ${cpu_type}/t-softfp t-softfp"
@@ -421,6 +426,11 @@ arm*-*-fuchsia*)
 arm*-*-netbsdelf*)
 	tmake_file="$tmake_file arm/t-arm arm/t-netbsd t-slibgcc-gld-nover"
 	;;
+arm-*-openbsd*)
+	tmake_file="$tmake_file arm/t-arm arm/t-elf arm/t-bpabi"
+	tmake_file="$tmake_file t-softfp-sfdf t-softfp-excl arm/t-softfp t-softfp"
+	unwind_header=config/arm/unwind-arm.h
+	;;
 arm*-*-linux*)			# ARM GNU/Linux with ELF
 	tmake_file="${tmake_file} arm/t-arm t-fixedpoint-gnu-prefix t-crtfm"
 	tmake_file="${tmake_file} arm/t-elf arm/t-bpabi arm/t-linux-eabi t-slibgcc-libgcc"
@@ -882,6 +892,12 @@ microblaze*-*-rtems*)
 	;;
 mips*-*-netbsd*)			# NetBSD/mips, either endian.
 	;;
+mips64-*-openbsd*)
+       set
+       ;;
+mips64el-*-openbsd*)
+       set
+       ;;
 mips*-*-linux*)				# Linux MIPS, either endian.
 	extra_parts="$extra_parts crtfastmath.o"
 	tmake_file="${tmake_file} t-crtfm"
@@ -1037,6 +1053,9 @@ powerpc*-*-freebsd*)
 	;;
 powerpc-*-netbsd*)
 	tmake_file="$tmake_file rs6000/t-netbsd rs6000/t-crtstuff"
+	;;
+powerpc*-*-openbsd*)
+	tmake_file="${tmake_file} rs6000/t-ppccomm rs6000/t-crtstuff rs6000/t-openbsd"
 	;;
 powerpc-*-eabispe*)
 	tmake_file="${tmake_file} rs6000/t-ppccomm rs6000/t-savresfgpr rs6000/t-crtstuff t-crtstuff-pic t-fdpbit"