diff --git a/configure.ac b/configure.ac
index 964ef03..eb5a3ad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -40,6 +40,37 @@ AC_COMPILE_IFELSE([AC_LANG_SOURCE([char foo;])],
 CFLAGS="$saved_CFLAGS"
 AC_SUBST(SYMBOL_VISIBILITY)
 
+AC_ARG_ENABLE(sanitize,
+	[AS_HELP_STRING(
+		[--enable-sanitize],
+		[Compile with address sanitizer enabled],
+	)],
+	[sanitize=$enableval], [sanitize="no"])
+if test x"$sanitize" = x"yes"
+then
+	CFLAGS="$CFLAGS -fsanitize=address -fsanitize=undefined"
+	CPPFLAGS="$CPPFLAGS -fsanitize=address -fsanitize=undefined"
+fi
+
+AC_ARG_ENABLE(werror,
+	[AS_HELP_STRING(
+		[--enable-werror],
+		[Turn all compiler warnings into errors, with exceptions:
+		 a) deprecation (allow upstream to mark deprecation without breaking builds);
+		 b) "#warning" pragmas (allow to remind ourselves of errors without breaking builds)
+		]
+	)],
+	[werror=$enableval], [werror="no"])
+if test x"$werror" = x"yes"
+then
+	WERROR_FLAGS="-Werror"
+	WERROR_FLAGS+=" -Wno-error=deprecated -Wno-error=deprecated-declarations"
+	WERROR_FLAGS+=" -Wno-error=cpp" # "#warning"
+	CFLAGS="$CFLAGS $WERROR_FLAGS"
+	CPPFLAGS="$CPPFLAGS $WERROR_FLAGS"
+fi
+
+
 dnl Generate the output
 AC_CONFIG_HEADER(config.h)
 
diff --git a/git-version-gen b/git-version-gen
index 42cf3d2..2a9abb5 100755
--- a/git-version-gen
+++ b/git-version-gen
@@ -93,8 +93,8 @@ if test -n "$v"
 then
     : # use $v
 elif
-       v=`git describe --abbrev=4 --match='v*' HEAD 2>/dev/null \
-	  || git describe --abbrev=4 HEAD 2>/dev/null` \
+       v=`git describe --abbrev=4 HEAD 2>/dev/null \
+	  || git describe --abbrev=4 --match='v*' HEAD 2>/dev/null` \
     && case $v in
 	 [0-9]*) ;;
 	 v[0-9]*) ;;