Implement --enable-sanitizers[=sanitizers]

Similar to debugging with Valgrind, it's very useful to enable
-fsanitize= switches to catch bugs at runtime.

$ ./configure
Result: no sanitizer enabled

$ ./configure --enable-sanitizers
Result: -fsanitize=address,undefined

$ ./configure --enable-sanitizers=address,thread,undefined
Result: -fsanitize=address,thread,undefined

$ ./configure --enable-sanitizers=undefined
Result: -fsanitize=undefined

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/odbc/configure.in b/lib/odbc/configure.in
index f86146759c..ea5c51965f 100644
--- a/lib/odbc/configure.in
+++ b/lib/odbc/configure.in
@@ -228,4 +228,24 @@ if test "x$GCC" = xyes; then
     LM_TRY_ENABLE_CFLAG([-Werror=return-type], [CFLAGS])
 fi
 
+dnl ----------------------------------------------------------------------
+dnl Enable -fsanitize= flags.
+dnl ----------------------------------------------------------------------
+
+m4_define(DEFAULT_SANITIZERS, [address,undefined])
+AC_ARG_ENABLE(
+    sanitizers,
+    AS_HELP_STRING(
+        [--enable-sanitizers@<:@=comma-separated list of sanitizers@:>@],
+	    [Default=DEFAULT_SANITIZERS]),
+[
+case "$enableval" in
+    no) sanitizers= ;;
+    yes) sanitizers="-fsanitize=DEFAULT_SANITIZERS" ;;
+    *) sanitizers="-fsanitize=$enableval" ;;
+esac
+CFLAGS="$CFLAGS $sanitizers"
+LDFLAGS="$LDFLAGS $sanitizers"
+])
+
 AC_OUTPUT(c_src/$host/Makefile:c_src/Makefile.in)