patch 8.0.0398: illegal memory access with "t"

Problem:    Illegal memory access with "t".
Solution:   Use strncmp() instead of memcmp(). (Dominique Pelle, closes #1528)
diff --git a/src/search.c b/src/search.c
index 83c5842..d23dde2 100644
--- a/src/search.c
+++ b/src/search.c
@@ -1693,12 +1693,9 @@
 		    if (p[col] == c && stop)
 			break;
 		}
-		else
-		{
-		    if (memcmp(p + col, lastc_bytes, lastc_bytelen) == 0
+		else if (STRNCMP(p + col, lastc_bytes, lastc_bytelen) == 0
 								       && stop)
-			break;
-		}
+		    break;
 		stop = TRUE;
 	    }
 	}
diff --git a/src/testdir/test_search.vim b/src/testdir/test_search.vim
index 040a809..1a114c4 100644
--- a/src/testdir/test_search.vim
+++ b/src/testdir/test_search.vim
@@ -294,3 +294,10 @@
   q!
 endfunc
 
+func Test_searchc()
+  " These commands used to cause memory overflow in searchc().
+  new
+  norm ixx
+  exe "norm 0t\u93cf"
+  bw!
+endfunc
diff --git a/src/version.c b/src/version.c
index 26b5455..c1f426c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    398,
+/**/
     397,
 /**/
     396,