Re: [PATCH] Fix compile-cplus-types.c build errors

[Simon Marchi <simon dot marchi at ericsson dot com>]

On 2018-08-30 11:06 AM, Tom Tromey wrote:
>>>>>> "Simon" == Simon Marchi <simon.marchi@ericsson.com> writes:
> 
> Simon> Fix the third one by comparing to 0 instead.  I think the current
> Simon> comparison simply uses the wrong enum type.  Comparing to 0 seems like
> Simon> the right thing to do, because we want to check whether any flags are
> Simon> specified.
> 
> I think this is fine, but at the same time, it seems reasonable to me to
> want to compare an enum flags object against an enumerator from the
> underlying type.  So maybe enum_flags should have operator== and operator!=.
> 
> What do you think of this?  I am trying to think of a counter-example
> where this would cause problems.

I think this is already possible (but I have not tested).  In this case, it's
actually comparing against an enumerator from a completely different enum type.

Here's what I pushed.  Keith has already fixed the first error, this fixes the
others.

@Joel, I used host_address_to_string.


>From a0dc02a6df86011462293cc11b4e35c0f18effd0 Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@ericsson.com>
Date: Thu, 30 Aug 2018 11:09:48 -0400
Subject: [PATCH] Fix compile-cplus-types.c build errors

I see these errors when building with clang:

  CXX    compile/compile-cplus-types.o
/home/emaisin/src/binutils-gdb/gdb/compile/compile-cplus-types.c:306:56: error: cannot pass non-trivial object of type 'compile_scope' to variadic function; expected type from format string was 'void *' [-Wnon-pod-varargs]
        fprintf_unfiltered (gdb_stdlog, "leaving scope %p\n", current);
                                                       ~~     ^~~~~~~
/home/emaisin/src/binutils-gdb/gdb/compile/compile-cplus-types.c:1058:13: error: comparison of two values with different enumeration types ('enum_flags<gcc_cp_qualifiers>::enum_type' (aka 'gcc_cp_qualifiers') and 'gcc_cp_ref_qualifiers') [-Werror,-Wenum-compare]
  if (quals != GCC_CP_REF_QUAL_NONE)
      ~~~~~ ^  ~~~~~~~~~~~~~~~~~~~~

Fix the first one by using host_address_to_string.

Fix the second one by comparing to 0 instead.  I think the current
comparison simply uses the wrong enum type.  Comparing to 0 seems like
the right thing to do, because we want to check whether any flags are
specified.

gdb/ChangeLog:

	* compile/compile-cplus-types.c
	(compile_cplus_instance::leave_scope): Take the address of scope
	object.
	(compile_cplus_instance::convert_qualified_base): Compare quals
	to 0.
---
 gdb/ChangeLog                     | 8 ++++++++
 gdb/compile/compile-cplus-types.c | 7 +++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2e59caf..66c2e33 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2018-08-30  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* compile/compile-cplus-types.c
+	(compile_cplus_instance::leave_scope): Take the address of scope
+	object.
+	(compile_cplus_instance::convert_qualified_base): Compare quals
+	to 0.
+
 2018-08-30  Keith Seitz  <keiths@redhat.com>

 	* compile/compile-cplus-types.c (compile_cplus_instance::enter_scope):
diff --git a/gdb/compile/compile-cplus-types.c b/gdb/compile/compile-cplus-types.c
index e86a573..7fc4136 100644
--- a/gdb/compile/compile-cplus-types.c
+++ b/gdb/compile/compile-cplus-types.c
@@ -306,7 +306,10 @@ compile_cplus_instance::leave_scope ()
   if (current.m_pushed)
     {
       if (debug_compile_cplus_scopes)
-	fprintf_unfiltered (gdb_stdlog, "leaving scope %p\n", current);
+	{
+	  fprintf_unfiltered (gdb_stdlog, "leaving scope %s\n",
+			      host_address_to_string (&current));
+	}

       /* Pop namespaces.  */
       std::for_each
@@ -1058,7 +1061,7 @@ compile_cplus_instance::convert_qualified_base (gcc_type base,
 {
   gcc_type result = base;

-  if (quals != GCC_CP_REF_QUAL_NONE)
+  if (quals != 0)
     result = plugin ().build_qualified_type (base, quals);

   return result;
-- 
2.7.4