[PATCH] Fix ICU miscompilation due to tree-ssa-strlen.c bug (PR tree-optimization/88693)

[Bernd Edlinger]

Hi,

co-incidentally my "Make strlen range computations more conservative" patch
contained a fix on the same spot, I just did not have a test case for it:

@@ -3184,7 +3146,10 @@ get_min_string_length (tree rhs, bool *f
       && TREE_READONLY (rhs))
     rhs = DECL_INITIAL (rhs);

-  if (rhs && TREE_CODE (rhs) == STRING_CST)
+  if (rhs && TREE_CODE (rhs) == STRING_CST
+      && tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (rhs)))) == 1
+      && TREE_STRING_LENGTH (rhs) > 0
+      && TREE_STRING_POINTER (rhs) [TREE_STRING_LENGTH (rhs) - 1] == '\0')
     {
       *full_string_p = true;
       return strlen (TREE_STRING_POINTER (rhs));


additionally to your patch this tests the string is in fact a single-byte string.
since strlen returns garbage otherwise.


Bernd.