diff --git a/config.c b/config.c
index f9c400ad30..3cd10aeb90 100644
--- a/config.c
+++ b/config.c
@@ -1833,9 +1833,10 @@ static int git_config_from_blob_ref(config_fn_t fn,
 char *git_system_config(void)
 {
 	char *system_config = xstrdup_or_null(getenv("GIT_CONFIG_SYSTEM"));
-	if (system_config)
-		return system_config;
-	return system_path(ETC_GITCONFIG);
+	if (!system_config)
+		system_config = system_path(ETC_GITCONFIG);
+	normalize_path_copy(system_config, system_config);
+	return system_config;
 }
 
 void git_global_config(char **user_out, char **xdg_out)
diff --git a/config.mak.uname b/config.mak.uname
index cb443b4e02..0587a23c1c 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -437,6 +437,11 @@ ifeq ($(uname_S),Windows)
 	NO_POSIX_GOODIES = UnfortunatelyYes
 	NATIVE_CRLF = YesPlease
 	DEFAULT_HELP_FORMAT = html
+ifeq (/mingw64,$(subst 32,64,$(prefix)))
+	# Move system config into top-level /etc/
+	ETC_GITCONFIG = ../etc/gitconfig
+	ETC_GITATTRIBUTES = ../etc/gitattributes
+endif
 
 	CC = compat/vcbuild/scripts/clink.pl
 	AR = compat/vcbuild/scripts/lib.pl
@@ -671,6 +676,11 @@ else
 		USE_LIBPCRE= YesPlease
 		NO_CURL =
 		USE_NED_ALLOCATOR = YesPlease
+		ifeq (/mingw64,$(subst 32,64,$(prefix)))
+			# Move system config into top-level /etc/
+			ETC_GITCONFIG = ../etc/gitconfig
+			ETC_GITATTRIBUTES = ../etc/gitattributes
+		endif
 	else
 		COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO
 		NO_CURL = YesPlease
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 3dc7ffcd98..171b4124af 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -223,8 +223,6 @@ list(APPEND compat_SOURCES sha1dc_git.c sha1dc/sha1.c sha1dc/ubc_check.c block-s
 
 
 add_compile_definitions(PAGER_ENV="LESS=FRX LV=-c"
-			ETC_GITATTRIBUTES="etc/gitattributes"
-			ETC_GITCONFIG="etc/gitconfig"
 			GIT_EXEC_PATH="libexec/git-core"
 			GIT_LOCALE_PATH="share/locale"
 			GIT_MAN_PATH="share/man"
@@ -239,10 +237,15 @@ add_compile_definitions(PAGER_ENV="LESS=FRX LV=-c"
 
 if(WIN32)
 	set(FALLBACK_RUNTIME_PREFIX /mingw64)
-	add_compile_definitions(FALLBACK_RUNTIME_PREFIX="${FALLBACK_RUNTIME_PREFIX}")
+	# Move system config into top-level /etc/
+	add_compile_definitions(FALLBACK_RUNTIME_PREFIX="${FALLBACK_RUNTIME_PREFIX}"
+		ETC_GITATTRIBUTES="../etc/gitattributes"
+		ETC_GITCONFIG="../etc/gitconfig")
 else()
 	set(FALLBACK_RUNTIME_PREFIX /home/$ENV{USER})
-	add_compile_definitions(FALLBACK_RUNTIME_PREFIX="${FALLBACK_RUNTIME_PREFIX}")
+	add_compile_definitions(FALLBACK_RUNTIME_PREFIX="${FALLBACK_RUNTIME_PREFIX}"
+		ETC_GITATTRIBUTES="etc/gitattributes"
+		ETC_GITCONFIG="etc/gitconfig")
 endif()