Hi,

I updated gimple-fold.c as you suggested, bootstrapped and re-tested on both 
x86 and aarch64. no any issue.

====
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index 353a46e..eb6a87a 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -1323,6 +1323,19 @@ get_range_strlen (tree arg, tree length[2], bitmap 
*visited, int type,
                 the array could have zero length.  */
              *minlen = ssize_int (0);
            }
+
+         if (VAR_P (arg) 
+             && TREE_CODE (TREE_TYPE (arg)) == ARRAY_TYPE)
+           {
+             val = TYPE_SIZE_UNIT (TREE_TYPE (arg));
+             if (!val || TREE_CODE (val) != INTEGER_CST || integer_zerop (val))
+               return false;
+             val = wide_int_to_tree (TREE_TYPE (val), 
+                                     wi::sub(wi::to_wide (val), 1));
+             /* Set the minimum size to zero since the string in
+                the array could have zero length.  */
+             *minlen = ssize_int (0);
+           }
        }
====

I plan to commit the change very soon. 
let me know if you have further comment.

thanks.

Qing

==========

the updated full patch is as following:

gcc/ChangeLog

2017-12-13  Qing Zhao  <qing.z...@oracle.com >

     PR middle_end/79538
     * gimple-fold.c (get_range_strlen): Add the handling of non-member array.

gcc/fortran/ChangeLog

2017-12-13  Qing Zhao  <qing.z...@oracle.com >

      PR middle_end/79538
      * class.c (gfc_build_class_symbol): Replace call to
      sprintf with xasprintf to avoid format-overflow warning.
      (generate_finalization_wrapper): Likewise.
      (gfc_find_derived_vtab): Likewise.
      (find_intrinsic_vtab): Likewise.


gcc/c-family/ChangeLog

2017-12-13  Qing Zhao  <qing.z...@oracle.com >

     PR middle_end/79538 
        * c-cppbuiltin.c (builtin_define_with_hex_fp_value):
     Adjust the size of buf1 and buf2, add a new buf to avoid
     format-overflow warning.

gcc/testsuite/ChangeLog

2017-12-13  Qing Zhao  <qing.z...@oracle.com >

     PR middle_end/79538
     * gcc.dg/pr79538.c: New test.

---
 gcc/c-family/c-cppbuiltin.c    | 10 ++++-----
 gcc/fortran/class.c            | 49 ++++++++++++++++++++++++------------------
 gcc/gimple-fold.c              | 13 +++++++++++
 gcc/testsuite/gcc.dg/pr79538.c | 23 ++++++++++++++++++++
 4 files changed, 69 insertions(+), 26 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/pr79538.c

diff --git a/gcc/c-family/c-cppbuiltin.c b/gcc/c-family/c-cppbuiltin.c
index 2ac9616..9e33aed 100644
--- a/gcc/c-family/c-cppbuiltin.c
+++ b/gcc/c-family/c-cppbuiltin.c
@@ -1613,7 +1613,7 @@ builtin_define_with_hex_fp_value (const char *macro,
                                  const char *fp_cast)
 {
   REAL_VALUE_TYPE real;
-  char dec_str[64], buf1[256], buf2[256];
+  char dec_str[64], buf[256], buf1[128], buf2[64];
 
   /* This is very expensive, so if possible expand them lazily.  */
   if (lazy_hex_fp_value_count < 12
@@ -1656,11 +1656,11 @@ builtin_define_with_hex_fp_value (const char *macro,
 
   /* Assemble the macro in the following fashion
      macro = fp_cast [dec_str fp_suffix] */
-  sprintf (buf1, "%s%s", dec_str, fp_suffix);
-  sprintf (buf2, fp_cast, buf1);
-  sprintf (buf1, "%s=%s", macro, buf2);
+  sprintf (buf2, "%s%s", dec_str, fp_suffix);
+  sprintf (buf1, fp_cast, buf2);
+  sprintf (buf, "%s=%s", macro, buf1);
 
-  cpp_define (parse_in, buf1);
+  cpp_define (parse_in, buf);
 }
 
 /* Return a string constant for the suffix for a value of type TYPE
diff --git a/gcc/fortran/class.c b/gcc/fortran/class.c
index ebbd41b..a08fb8d 100644
--- a/gcc/fortran/class.c
+++ b/gcc/fortran/class.c
@@ -602,7 +602,8 @@ bool
 gfc_build_class_symbol (gfc_typespec *ts, symbol_attribute *attr,
                        gfc_array_spec **as)
 {
-  char name[GFC_MAX_SYMBOL_LEN+1], tname[GFC_MAX_SYMBOL_LEN+1];
+  char tname[GFC_MAX_SYMBOL_LEN+1];
+  char *name;
   gfc_symbol *fclass;
   gfc_symbol *vtab;
   gfc_component *c;
@@ -633,17 +634,17 @@ gfc_build_class_symbol (gfc_typespec *ts, 
symbol_attribute *attr,
   rank = !(*as) || (*as)->rank == -1 ? GFC_MAX_DIMENSIONS : (*as)->rank;
   get_unique_hashed_string (tname, ts->u.derived);
   if ((*as) && attr->allocatable)
-    sprintf (name, "__class_%s_%d_%da", tname, rank, (*as)->corank);
+    name = xasprintf ("__class_%s_%d_%da", tname, rank, (*as)->corank);
   else if ((*as) && attr->pointer)
-    sprintf (name, "__class_%s_%d_%dp", tname, rank, (*as)->corank);
+    name = xasprintf ("__class_%s_%d_%dp", tname, rank, (*as)->corank);
   else if ((*as))
-    sprintf (name, "__class_%s_%d_%dt", tname, rank, (*as)->corank);
+    name = xasprintf ("__class_%s_%d_%dt", tname, rank, (*as)->corank);
   else if (attr->pointer)
-    sprintf (name, "__class_%s_p", tname);
+    name = xasprintf ("__class_%s_p", tname);
   else if (attr->allocatable)
-    sprintf (name, "__class_%s_a", tname);
+    name = xasprintf ("__class_%s_a", tname);
   else
-    sprintf (name, "__class_%s_t", tname);
+    name = xasprintf ("__class_%s_t", tname);
 
   if (ts->u.derived->attr.unlimited_polymorphic)
     {
@@ -738,6 +739,7 @@ gfc_build_class_symbol (gfc_typespec *ts, symbol_attribute 
*attr,
   ts->u.derived = fclass;
   attr->allocatable = attr->pointer = attr->dimension = attr->codimension = 0;
   (*as) = NULL;
+  free (name);
   return true;
 }
 
@@ -1527,7 +1529,7 @@ generate_finalization_wrapper (gfc_symbol *derived, 
gfc_namespace *ns,
   gfc_component *comp;
   gfc_namespace *sub_ns;
   gfc_code *last_code, *block;
-  char name[GFC_MAX_SYMBOL_LEN+1];
+  char *name;
   bool finalizable_comp = false;
   bool expr_null_wrapper = false;
   gfc_expr *ancestor_wrapper = NULL, *rank;
@@ -1606,7 +1608,7 @@ generate_finalization_wrapper (gfc_symbol *derived, 
gfc_namespace *ns,
   sub_ns->resolved = 1;
 
   /* Set up the procedure symbol.  */
-  sprintf (name, "__final_%s", tname);
+  name = xasprintf ("__final_%s", tname);
   gfc_get_symbol (name, sub_ns, &final);
   sub_ns->proc_name = final;
   final->attr.flavor = FL_PROCEDURE;
@@ -2172,6 +2174,7 @@ generate_finalization_wrapper (gfc_symbol *derived, 
gfc_namespace *ns,
   gfc_free_expr (rank);
   vtab_final->initializer = gfc_lval_expr_from_sym (final);
   vtab_final->ts.interface = final;
+  free (name);
 }
 
 
@@ -2239,10 +2242,11 @@ gfc_find_derived_vtab (gfc_symbol *derived)
 
   if (ns)
     {
-      char name[GFC_MAX_SYMBOL_LEN+1], tname[GFC_MAX_SYMBOL_LEN+1];
+      char tname[GFC_MAX_SYMBOL_LEN+1];
+      char *name;
 
       get_unique_hashed_string (tname, derived);
-      sprintf (name, "__vtab_%s", tname);
+      name = xasprintf ("__vtab_%s", tname);
 
       /* Look for the vtab symbol in various namespaces.  */
       if (gsym && gsym->ns)
@@ -2270,7 +2274,7 @@ gfc_find_derived_vtab (gfc_symbol *derived)
          vtab->attr.vtab = 1;
          vtab->attr.access = ACCESS_PUBLIC;
          gfc_set_sym_referenced (vtab);
-         sprintf (name, "__vtype_%s", tname);
+         name = xasprintf ("__vtype_%s", tname);
 
          gfc_find_symbol (name, ns, 0, &vtype);
          if (vtype == NULL)
@@ -2373,7 +2377,7 @@ gfc_find_derived_vtab (gfc_symbol *derived)
              else
                {
                  /* Construct default initialization variable.  */
-                 sprintf (name, "__def_init_%s", tname);
+                 name = xasprintf ("__def_init_%s", tname);
                  gfc_get_symbol (name, ns, &def_init);
                  def_init->attr.target = 1;
                  def_init->attr.artificial = 1;
@@ -2406,7 +2410,7 @@ gfc_find_derived_vtab (gfc_symbol *derived)
                  ns->contained = sub_ns;
                  sub_ns->resolved = 1;
                  /* Set up procedure symbol.  */
-                 sprintf (name, "__copy_%s", tname);
+                 name = xasprintf ("__copy_%s", tname);
                  gfc_get_symbol (name, sub_ns, &copy);
                  sub_ns->proc_name = copy;
                  copy->attr.flavor = FL_PROCEDURE;
@@ -2483,7 +2487,7 @@ gfc_find_derived_vtab (gfc_symbol *derived)
                  ns->contained = sub_ns;
                  sub_ns->resolved = 1;
                  /* Set up procedure symbol.  */
-                 sprintf (name, "__deallocate_%s", tname);
+                 name = xasprintf ("__deallocate_%s", tname);
                  gfc_get_symbol (name, sub_ns, &dealloc);
                  sub_ns->proc_name = dealloc;
                  dealloc->attr.flavor = FL_PROCEDURE;
@@ -2532,6 +2536,7 @@ have_vtype:
          vtab->ts.u.derived = vtype;
          vtab->value = gfc_default_initializer (&vtab->ts);
        }
+      free (name);
     }
 
   found_sym = vtab;
@@ -2623,13 +2628,14 @@ find_intrinsic_vtab (gfc_typespec *ts)
 
   if (ns)
     {
-      char name[GFC_MAX_SYMBOL_LEN+1], tname[GFC_MAX_SYMBOL_LEN+1];
-
+      char tname[GFC_MAX_SYMBOL_LEN+1];
+      char *name;
+      
       /* Encode all types as TYPENAME_KIND_ including especially character
         arrays, whose length is now consistently stored in the _len component
         of the class-variable.  */
       sprintf (tname, "%s_%d_", gfc_basic_typename (ts->type), ts->kind);
-      sprintf (name, "__vtab_%s", tname);
+      name = xasprintf ("__vtab_%s", tname);
 
       /* Look for the vtab symbol in the top-level namespace only.  */
       gfc_find_symbol (name, ns, 0, &vtab);
@@ -2646,7 +2652,7 @@ find_intrinsic_vtab (gfc_typespec *ts)
          vtab->attr.vtab = 1;
          vtab->attr.access = ACCESS_PUBLIC;
          gfc_set_sym_referenced (vtab);
-         sprintf (name, "__vtype_%s", tname);
+         name = xasprintf ("__vtype_%s", tname);
 
          gfc_find_symbol (name, ns, 0, &vtype);
          if (vtype == NULL)
@@ -2722,12 +2728,12 @@ find_intrinsic_vtab (gfc_typespec *ts)
              c->tb->ppc = 1;
 
              if (ts->type != BT_CHARACTER)
-               sprintf (name, "__copy_%s", tname);
+               name = xasprintf ("__copy_%s", tname);
              else
                {
                  /* __copy is always the same for characters.
                     Check to see if copy function already exists.  */
-                 sprintf (name, "__copy_character_%d", ts->kind);
+                 name = xasprintf ("__copy_character_%d", ts->kind);
                  contained = ns->contained;
                  for (; contained; contained = contained->sibling)
                    if (contained->proc_name
@@ -2796,6 +2802,7 @@ find_intrinsic_vtab (gfc_typespec *ts)
          vtab->ts.u.derived = vtype;
          vtab->value = gfc_default_initializer (&vtab->ts);
        }
+      free (name);
     }
 
   found_sym = vtab;
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index 353a46e..eb6a87a 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -1323,6 +1323,19 @@ get_range_strlen (tree arg, tree length[2], bitmap 
*visited, int type,
                 the array could have zero length.  */
              *minlen = ssize_int (0);
            }
+
+         if (VAR_P (arg) 
+             && TREE_CODE (TREE_TYPE (arg)) == ARRAY_TYPE)
+           {
+             val = TYPE_SIZE_UNIT (TREE_TYPE (arg));
+             if (!val || TREE_CODE (val) != INTEGER_CST || integer_zerop (val))
+               return false;
+             val = wide_int_to_tree (TREE_TYPE (val), 
+                                     wi::sub(wi::to_wide (val), 1));
+             /* Set the minimum size to zero since the string in
+                the array could have zero length.  */
+             *minlen = ssize_int (0);
+           }
        }
 
       if (!val)
diff --git a/gcc/testsuite/gcc.dg/pr79538.c b/gcc/testsuite/gcc.dg/pr79538.c
new file mode 100644
index 0000000..c5a631e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr79538.c
@@ -0,0 +1,23 @@
+/* PR middle-end/79538 - missing -Wformat-overflow with %s and non-member 
array arguments
+   { dg-do compile }
+   { dg-options "-O2 -Wformat-overflow" } */
+
+char a3[3];
+char a4[4];
+char d[3];
+
+void g (int i)
+{
+  const char *s = i < 0 ? a3 : a4;
+  __builtin_sprintf (d, "%s", s);      /* { dg-warning ".__builtin_sprintf. 
may write a terminating nul past the end of the destination" } */
+  return;
+}
+
+void f ()
+{
+  char des[3];
+  char src[] = "abcd";
+  __builtin_sprintf (des, "%s", src); /* { dg-warning "directive writing up to 
4 bytes into a region of size 3" } */
+  return;
+}
+
-- 
1.9.1


> On Dec 12, 2017, at 10:50 AM, Richard Biener <rguent...@suse.de> wrote:
>>> 
>> 
>> Okay.
>>> 
>>>> +                return false;
>>>> +              val = fold_build2 (MINUS_EXPR, TREE_TYPE (val), val,
>>>> +                                 integer_one_node);
>>> 
>>>  val = wide_int_to_tree (TREE_TYPE (val), wi::minus (wi::to_wide
>> (val), 1));
> 
> I don't see this requested change. 
> 

Reply via email to