diff --git a/configure b/configure
index 7790025301401..9cf3e0be87373 100755
--- a/configure
+++ b/configure
@@ -883,7 +883,10 @@ CFG_PREFIX=${CFG_PREFIX%/}
 CFG_MANDIR=${CFG_MANDIR%/}
 CFG_HOST="$(echo $CFG_HOST | tr ',' ' ')"
 CFG_TARGET="$(echo $CFG_TARGET | tr ',' ' ')"
-CFG_SUPPORTED_TARGET="$(ls ${CFG_SRC_DIR}mk/cfg)"
+CFG_SUPPORTED_TARGET=""
+for target_file in ${CFG_SRC_DIR}mk/cfg/*.mk; do
+  CFG_SUPPORTED_TARGET="${CFG_SUPPORTED_TARGET} $(basename "$target_file" .mk)"
+done
 
 # copy host-triples to target-triples so that hosts are a subset of targets
 V_TEMP=""
diff --git a/mk/cfg/arm-apple-ios b/mk/cfg/arm-apple-ios.mk
similarity index 100%
rename from mk/cfg/arm-apple-ios
rename to mk/cfg/arm-apple-ios.mk
diff --git a/mk/cfg/arm-linux-androideabi b/mk/cfg/arm-linux-androideabi.mk
similarity index 100%
rename from mk/cfg/arm-linux-androideabi
rename to mk/cfg/arm-linux-androideabi.mk
diff --git a/mk/cfg/arm-unknown-linux-gnueabi b/mk/cfg/arm-unknown-linux-gnueabi.mk
similarity index 100%
rename from mk/cfg/arm-unknown-linux-gnueabi
rename to mk/cfg/arm-unknown-linux-gnueabi.mk
diff --git a/mk/cfg/arm-unknown-linux-gnueabihf b/mk/cfg/arm-unknown-linux-gnueabihf.mk
similarity index 100%
rename from mk/cfg/arm-unknown-linux-gnueabihf
rename to mk/cfg/arm-unknown-linux-gnueabihf.mk
diff --git a/mk/cfg/i386-apple-ios b/mk/cfg/i386-apple-ios.mk
similarity index 100%
rename from mk/cfg/i386-apple-ios
rename to mk/cfg/i386-apple-ios.mk
diff --git a/mk/cfg/i686-apple-darwin b/mk/cfg/i686-apple-darwin.mk
similarity index 100%
rename from mk/cfg/i686-apple-darwin
rename to mk/cfg/i686-apple-darwin.mk
diff --git a/mk/cfg/i686-pc-windows-gnu b/mk/cfg/i686-pc-windows-gnu.mk
similarity index 100%
rename from mk/cfg/i686-pc-windows-gnu
rename to mk/cfg/i686-pc-windows-gnu.mk
diff --git a/mk/cfg/i686-unknown-linux-gnu b/mk/cfg/i686-unknown-linux-gnu.mk
similarity index 100%
rename from mk/cfg/i686-unknown-linux-gnu
rename to mk/cfg/i686-unknown-linux-gnu.mk
diff --git a/mk/cfg/mips-unknown-linux-gnu b/mk/cfg/mips-unknown-linux-gnu.mk
similarity index 100%
rename from mk/cfg/mips-unknown-linux-gnu
rename to mk/cfg/mips-unknown-linux-gnu.mk
diff --git a/mk/cfg/mipsel-unknown-linux-gnu b/mk/cfg/mipsel-unknown-linux-gnu.mk
similarity index 100%
rename from mk/cfg/mipsel-unknown-linux-gnu
rename to mk/cfg/mipsel-unknown-linux-gnu.mk
diff --git a/mk/cfg/x86_64-apple-darwin b/mk/cfg/x86_64-apple-darwin.mk
similarity index 100%
rename from mk/cfg/x86_64-apple-darwin
rename to mk/cfg/x86_64-apple-darwin.mk
diff --git a/mk/cfg/x86_64-pc-windows-gnu b/mk/cfg/x86_64-pc-windows-gnu.mk
similarity index 100%
rename from mk/cfg/x86_64-pc-windows-gnu
rename to mk/cfg/x86_64-pc-windows-gnu.mk
diff --git a/mk/cfg/x86_64-unknown-dragonfly b/mk/cfg/x86_64-unknown-dragonfly.mk
similarity index 100%
rename from mk/cfg/x86_64-unknown-dragonfly
rename to mk/cfg/x86_64-unknown-dragonfly.mk
diff --git a/mk/cfg/x86_64-unknown-freebsd b/mk/cfg/x86_64-unknown-freebsd.mk
similarity index 100%
rename from mk/cfg/x86_64-unknown-freebsd
rename to mk/cfg/x86_64-unknown-freebsd.mk
diff --git a/mk/cfg/x86_64-unknown-linux-gnu b/mk/cfg/x86_64-unknown-linux-gnu.mk
similarity index 100%
rename from mk/cfg/x86_64-unknown-linux-gnu
rename to mk/cfg/x86_64-unknown-linux-gnu.mk
diff --git a/mk/platform.mk b/mk/platform.mk
index 6da01efcaaad2..7ca24736cb859 100644
--- a/mk/platform.mk
+++ b/mk/platform.mk
@@ -113,7 +113,7 @@ $(foreach cvar,CC CXX CPP CFLAGS CXXFLAGS CPPFLAGS, \
 
 CFG_RLIB_GLOB=lib$(1)-*.rlib
 
-include $(wildcard $(CFG_SRC_DIR)mk/cfg/*)
+include $(wildcard $(CFG_SRC_DIR)mk/cfg/*.mk)
 
 # The -Qunused-arguments sidesteps spurious warnings from clang
 define FILTER_FLAGS