[Bug c++/57709] -Wshadow is too strict / has false positives

["manu at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57709

--- Comment #9 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
Something has changed in the C++ FE in the meanwhile. Could you try with this
one?

Index: name-lookup.c
===================================================================
--- name-lookup.c       (revision 205004)
+++ name-lookup.c       (working copy)
@@ -1216,13 +1216,25 @@ pushdecl_maybe_friend_1 (tree x, bool is
              else
                member = NULL_TREE;

              if (member && !TREE_STATIC (member))
                {
-                 /* Location of previous decl is not useful in this case.  */
-                 warning (OPT_Wshadow, "declaration of %qD shadows a member of
'this'",
-                          x);
+                 if (BASELINK_P (member))
+                   member = BASELINK_FUNCTIONS (member);
+
+                 /* Do not warn if a variable shadows a function, unless
+                    the variable is a function or a pointer-to-function.  */
+                 if (!(TREE_CODE (member) == FUNCTION_DECL
+                      && TREE_CODE (x) != FUNCTION_DECL
+                      && !FUNCTION_POINTER_TYPE_P (TREE_TYPE (x)))) {
+                   if (warning_at (input_location,
+                                   OPT_Wshadow, "declaration of %qD shadows a
member of %qT",
+                                x, current_nonlambda_class_type ())
+                       && DECL_P(member))
+                     inform (DECL_SOURCE_LOCATION (member),
+                             "shadowed declaration is here");
+                 }
                }
              else if (oldglobal != NULL_TREE
                       && (VAR_P (oldglobal)
                            /* If the old decl is a type decl, only warn if the
                               old decl is an explicit typedef or if both the
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From: "charles.baylis at linaro dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/59142] [4.8 / 4.9 Regression] internal compiler error while compiling OpenCV 2.4.7
Date: Tue, 19 Nov 2013 17:00:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idY142

Charles Baylis <charles.baylis at linaro dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |charles.baylis at linaro dot org

--- Comment #5 from Charles Baylis <charles.baylis at linaro dot org> ---
Created attachment 31251
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id1251&actioníit
Reduced test case


I have attached a reduced test case (produced using c-reduce).

$ arm-unknown-linux-gnueabi-gcc -W -fPIC -O2 -c -mcpu=cortex-a9 -mthumb
reference/reduced.cpp

I did a git bisect, and that points to the problem being introduced in r172837