Add a configure flag for ASAN.

Makefile.am

@@ -41,6 +41,10 @@ endif
 AM_CPPFLAGS += -DDEBUG
 endif
 AM_CPPFLAGS += -iquote.
+if IS_ASAN
+AM_CFLAGS += -fsanitize=address
+AM_LDFLAGS += -fsanitize=address
+endif
 endif
 
 # Set flags for Solaris.

configure.ac

@@ -73,6 +73,15 @@ AC_ARG_ENABLE(
 )
 AM_CONDITIONAL(IS_OPTIMIZED, test "x$enable_optimizations" = xyes)
 
+# Is this --enable-asan?
+AC_ARG_ENABLE(
+	asan,
+	AS_HELP_STRING(--enable-asan, enable ASAN build flags),
+	,
+	enable_asan=no
+)
+AM_CONDITIONAL(IS_ASAN, test "x$enable_asan" = xyes)
+
 # Is this a static build?
 AC_ARG_ENABLE(
 	static,