Index: Makefile.config.in
===================================================================
--- Makefile.config.in
+++ Makefile.config.in
@@ -117,6 +117,12 @@
 # Target operating system for which LLVM will compile for.
 TARGET_OS=@TARGET_OS@
 
+# Adjust paths for Bitrig
+ifeq ($(TARGET_OS),Bitrig)
+PROJ_docsdir    := $(PROJ_prefix)/share/docs/llvm
+PROJ_mandir     := $(PROJ_prefix)/man
+endif
+
 # Host hardware architecture
 HOST_ARCH=@HOST_ARCH@
 # Target hardware architecture
Index: autoconf/config.sub
===================================================================
--- autoconf/config.sub
+++ autoconf/config.sub
@@ -1354,7 +1354,7 @@
 	      | -os2* | -vos* | -palmos* | -uclinux* | -nucleus* \
 	      | -morphos* | -superux* | -rtmk* | -rtmk-nova* | -windiss* \
 	      | -powermax* | -dnix* | -nx6 | -nx7 | -sei* | -dragonfly* \
-	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops* | -es*)
+	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops* | -es* | -bitrig*)
 	# Remember, each alternative MUST END IN *, to match a version number.
 		;;
 	-qnx*)
Index: configure
===================================================================
--- configure
+++ configure
@@ -3966,6 +3966,11 @@
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
     llvm_cv_os_type="DragonFly"
     llvm_cv_platform_type="Unix" ;;
+  *-*-bitrig*)
+    llvm_cv_link_all_option="-Wl,--whole-archive"
+    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
+    llvm_cv_os_type="Bitrig"
+    llvm_cv_platform_type="Unix" ;;
   *-*-hpux*)
     llvm_cv_link_all_option="-Wl,--whole-archive"
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
@@ -4052,6 +4057,8 @@
     llvm_cv_target_os_type="NetBSD" ;;
   *-*-dragonfly*)
     llvm_cv_target_os_type="DragonFly" ;;
+  *-*-bitrig*)
+    llvm_cv_target_os_type="Bitrig" ;;
   *-*-hpux*)
     llvm_cv_target_os_type="HP-UX" ;;
   *-*-interix*)