re PR c++/35652 (offset warning should be given in the front-end)

gcc/

2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR c++/35652
	* builtins.h (c_strlen): Do not warn here.
	* c-typeck.c (build_binary_op): Adjust calls to pointer_int_sum.
	* c-common.c (pointer_int_sum): Take an explicit location.
	Warn about offsets out of bounds.
	* c-common.h (pointer_int_sum): Adjust declaration.

gcc/cp/

2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR c++/35652
	* typeck.c (cp_pointer_sum): Adjust call to pointer_int_sum.

gcc/testsuite/

2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR c++/35652
	* gcc.dg/pr35652.C: New.
	* g++.dg/warn/pr35652.C: New.
	* gcc.dg/format/plus-1.c: Adjust message.

From-SVN: r145102

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f5b7076..fbb0ae5 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,7 +1,16 @@
+2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+       PR c++/35652
+       * builtins.h (c_strlen): Do not warn here.
+       * c-typeck.c (build_binary_op): Adjust calls to pointer_int_sum.
+       * c-common.c (pointer_int_sum): Take an explicit location.
+       Warn about offsets out of bounds.
+       * c-common.h (pointer_int_sum): Adjust declaration.
+
 2009-03-26  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
-        * doc/invoke.texi (i386 and x86-64 Windows Options): Fix texinfo
-        markup glitch.
+       * doc/invoke.texi (i386 and x86-64 Windows Options): Fix texinfo
+       markup glitch.
 
 2009-03-26  Jakub Jelinek  <jakub@redhat.com>
 

diff --git a/gcc/builtins.c b/gcc/builtins.c
index cc9d93e..929ea90 100644 (file)
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -469,16 +469,13 @@ c_strlen (tree src, int only_value)
   else
     offset = tree_low_cst (offset_node, 0);
 
-  /* If the offset is known to be out of bounds, warn, and call strlen at
-     runtime.  */
+  /* If the offset is known to be out of bounds, the front-end should
+     have warned already. We call strlen at runtime.  
+
+     ??? Perhaps we should turn this into an assert and force
+     front-ends to define offsets whtin boundaries.  */
   if (offset < 0 || offset > max)
     {
-     /* Suppress multiple warnings for propagated constant strings.  */
-      if (! TREE_NO_WARNING (src))
-        {
-          warning (0, "offset outside bounds of constant string");
-          TREE_NO_WARNING (src) = 1;
-        }
       return NULL_TREE;
     }
 

diff --git a/gcc/c-common.c b/gcc/c-common.c
index cc00511..317c1d7 100644 (file)
--- a/gcc/c-common.c
+++ b/gcc/c-common.c
@@ -3211,7 +3211,8 @@ shorten_compare (tree *op0_ptr, tree *op1_ptr, tree *restype_ptr,
    of pointer PTROP and integer INTOP.  */
 
 tree
-pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
+pointer_int_sum (location_t location, enum tree_code resultcode,
+                tree ptrop, tree intop)
 {
   tree size_exp, ret;
 
@@ -3220,19 +3221,19 @@ pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
 
   if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
     {
-      pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
+      pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
               "pointer of type %<void *%> used in arithmetic");
       size_exp = integer_one_node;
     }
   else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
     {
-      pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
+      pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
               "pointer to a function used in arithmetic");
       size_exp = integer_one_node;
     }
   else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
     {
-      pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
+      pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith, 
               "pointer to member function used in arithmetic");
       size_exp = integer_one_node;
     }
@@ -3295,6 +3296,31 @@ pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
   if (resultcode == MINUS_EXPR)
     intop = fold_build1 (NEGATE_EXPR, sizetype, intop);
 
+  if (TREE_CODE (intop) == INTEGER_CST)
+    {
+      tree offset_node;
+      tree string_cst = string_constant (ptrop, &offset_node);
+
+      if (string_cst != 0 
+         && !(offset_node && TREE_CODE (offset_node) != INTEGER_CST))
+       {
+         HOST_WIDE_INT max = TREE_STRING_LENGTH (string_cst);
+         HOST_WIDE_INT offset;
+         if (offset_node == 0)
+           offset = 0;
+         else if (! host_integerp (offset_node, 0))
+           offset = -1;
+         else
+           offset = tree_low_cst (offset_node, 0);
+
+         offset = offset + tree_low_cst (intop, 0);
+         if (offset < 0 || offset > max)
+           warning_at (location, 0,
+                       "offset %<%ld%> outside bounds of constant string",
+                       tree_low_cst (intop, 0));
+       }
+    }
+
   ret = fold_build2 (POINTER_PLUS_EXPR, result_type, ptrop, intop);
 
   fold_undefer_and_ignore_overflow_warnings ();

diff --git a/gcc/c-common.h b/gcc/c-common.h
index 475c333..6ba33c6 100644 (file)
--- a/gcc/c-common.h
+++ b/gcc/c-common.h
@@ -746,7 +746,7 @@ extern tree shorten_binary_op (tree result_type, tree op0, tree op1, bool bitwis
    and, if so, perhaps change them both back to their original type.  */
 extern tree shorten_compare (tree *, tree *, tree *, enum tree_code *);
 
-extern tree pointer_int_sum (enum tree_code, tree, tree);
+extern tree pointer_int_sum (location_t, enum tree_code, tree, tree);
 
 /* Add qualifiers to a type, in the fashion for C.  */
 extern tree c_build_qualified_type (tree, int);

diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index f1d83f3..83188ba 100644 (file)
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -8107,12 +8107,12 @@ build_binary_op (location_t location, enum tree_code code,
       /* Handle the pointer + int case.  */
       if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
        {
-         ret = pointer_int_sum (PLUS_EXPR, op0, op1);
+         ret = pointer_int_sum (location, PLUS_EXPR, op0, op1);
          goto return_build_binary_op;
        }
       else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
        {
-         ret = pointer_int_sum (PLUS_EXPR, op1, op0);
+         ret = pointer_int_sum (location, PLUS_EXPR, op1, op0);
          goto return_build_binary_op;
        }
       else
@@ -8131,7 +8131,7 @@ build_binary_op (location_t location, enum tree_code code,
       /* Handle pointer minus int.  Just like pointer plus int.  */
       else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
        {
-         ret = pointer_int_sum (MINUS_EXPR, op0, op1);
+         ret = pointer_int_sum (location, MINUS_EXPR, op0, op1);
          goto return_build_binary_op;
        }
       else

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index bac3d7a..04977ae 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+       PR c++/35652
+       * typeck.c (cp_pointer_sum): Adjust call to pointer_int_sum.
+
 2009-03-26  Andrew Haley  <aph@redhat.com>
 
        PR C++/39380

diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index a6986f9..3788a7e 100644 (file)
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4031,7 +4031,7 @@ cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
      pointer_int_sum() anyway.  */
   complete_type (TREE_TYPE (res_type));
 
-  return pointer_int_sum (resultcode, ptrop,
+  return pointer_int_sum (input_location, resultcode, ptrop,
                          fold_if_not_in_template (intop));
 }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e3e6ab4..ea4b9c3 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2009-03-27  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+
+       PR c++/35652
+       * gcc.dg/pr35652.C: New.
+       * g++.dg/warn/pr35652.C: New.
+       * gcc.dg/format/plus-1.c: Adjust message.
+
 2009-03-26  Jakub Jelinek  <jakub@redhat.com>
 
        PR c++/39554
@@ -10,7 +17,7 @@
 
 2009-03-25  Alexander Monakov  <amonakov@ispras.ru>
 
-        * gcc.target/ia64/20090324-1.c: New test.
+       * gcc.target/ia64/20090324-1.c: New test.
 
 2009-03-25  Jakub Jelinek  <jakub@redhat.com>
 

diff --git a/gcc/testsuite/g++.dg/warn/pr35652.C b/gcc/testsuite/g++.dg/warn/pr35652.C
new file mode 100644 (file)
index 0000000..7ce9431
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/pr35652.C
@@ -0,0 +1,30 @@
+// PR c++/35652: wrong location and duplicated warning.
+// { dg-do compile }
+// { dg-options "-fshow-column" }
+#include <string>
+int foo() {
+  // blank line padding, could also be code...
+  //
+  //
+  //
+  //
+  //
+  //
+  //
+  //
+  //
+  std::string s = "";
+  s += 'x' + "y";  // { dg-warning "14:offset '120' outside bounds of constant string" }
+  // { dg-bogus "offset '120' outside bounds of constant string.*offset '120' outside bounds of constant string" "duplicated" { target *-*-* } 17 }
+}
+
+int bar()
+{
+  const char *s = 'z' + "y"; /* { dg-warning "25:offset '122' outside bounds of constant string" } */
+}
+
+int g()
+{
+  char str[2];
+  const char *p = str + sizeof(str);
+}

diff --git a/gcc/testsuite/gcc.dg/format/plus-1.c b/gcc/testsuite/gcc.dg/format/plus-1.c
index 02a213d..0d8b62c 100644 (file)
--- a/gcc/testsuite/gcc.dg/format/plus-1.c
+++ b/gcc/testsuite/gcc.dg/format/plus-1.c
@@ -15,6 +15,9 @@ foo (int i)
   printf (3 + "%d\n");         /* { dg-warning "zero-length" "zero-length string" } */
   printf ("%d\n" + i, i);      /* { dg-warning "not a string" "non-constant addend" } */
   printf ("%d\n" + 10);                /* { dg-warning "not a string" "too large addend" } */
+                                /* { dg-warning "offset '10' outside bounds of constant string" "offset" { target *-*-* } 17 } */
   printf ("%d\n" - 1, i);      /* { dg-warning "not a string" "minus constant" } */
+                                /* { dg-warning "offset '-1' outside bounds of constant string" "offset" { target *-*-* } 19 } */
   printf ("%d\n" + -1, i);     /* { dg-warning "not a string" "negative addend" } */
+                                /* { dg-warning "offset '-1' outside bounds of constant string" "offset" { target *-*-* } 21 } */
 }

diff --git a/gcc/testsuite/gcc.dg/pr35652.c b/gcc/testsuite/gcc.dg/pr35652.c
new file mode 100644 (file)
index 0000000..50ec3ac
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr35652.c
@@ -0,0 +1,13 @@
+/* PR c++/35652: wrong location and duplicated warning.
+ { dg-do compile }
+ { dg-options "" } */
+int bar()
+{
+  const char *s = 'z' + "y"; /* { dg-warning "offset '122' outside bounds of constant string" } */
+}
+
+int g()
+{
+  char str[2];
+  const char *p = str + sizeof(str);
+}