configure

@@ -194,9 +194,9 @@ if test "$gcc" -eq 1 && ($cc -c $test.c) >> configure.log 2>&1; then
   fi
   if test "$warn" -eq 1; then
     if test "$zconst" -eq 1; then
-      CFLAGS="${CFLAGS} -Wall -Wextra -Wcast-qual -pedantic -DZLIB_CONST"
+      CFLAGS="${CFLAGS} -Wall -Wextra -Wcast-qual -pedantic -DZLIB_CONST -fsanitize=address"
     else
-      CFLAGS="${CFLAGS} -Wall -Wextra -pedantic"
+      CFLAGS="${CFLAGS} -Wall -Wextra -pedantic -fsanitize=address"
     fi
   fi
   if test $debug -eq 1; then

inflate.c

@@ -1433,6 +1433,8 @@ z_streamp strm;
     /* return no joy or set up to restart inflate() on a new block */
     if (state->have != 4) return Z_DATA_ERROR;
+    if (state->mode == HEAD)
+        state->wrap = 0;    /* never processed header, so assume raw */
     in = strm->total_in;  out = strm->total_out;
     inflateReset(strm);
     strm->total_in = in;  strm->total_out = out;
@@ -1531,7 +1533,7 @@ int check;
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
-    if (check)
+    if (check && state->wrap)
         state->wrap |= 4;
     else
         state->wrap &= ~4;