diff --git a/config.mak.uname b/config.mak.uname
index 21f53e3f7e..3a90995587 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -465,14 +465,8 @@ ifeq ($(uname_S),Windows)
 	GIT_VERSION := $(GIT_VERSION).MSVC
 	pathsep = ;
 	# Assume that this is built in Git for Windows' SDK
-        ifeq (MINGW32,$(MSYSTEM))
-		prefix = /mingw32
-        else
-                ifeq (CLANGARM64,$(MSYSTEM))
-			prefix = /clangarm64
-                else
-			prefix = /mingw64
-                endif
+        ifneq (,$(MSYSTEM))
+		prefix = $(MINGW_PREFIX)
         endif
 	# Prepend MSVC 64-bit tool-chain to PATH.
 	#
@@ -755,6 +749,10 @@ ifeq ($(uname_S),MINGW)
 		BASIC_LDFLAGS += -Wl,--dynamicbase
         endif
         ifneq (,$(MSYSTEM))
+                ifeq ($(MINGW_PREFIX),$(filter-out /%,$(MINGW_PREFIX)))
+			# Override if empty or does not start with a slash
+			MINGW_PREFIX := /$(shell echo '$(MSYSTEM)' | tr A-Z a-z)
+                endif
 		prefix = $(MINGW_PREFIX)
 		HOST_CPU = $(patsubst %-w64-mingw32,%,$(MINGW_CHOST))
 		BASIC_LDFLAGS += -Wl,--pic-executable