Bug 19023 - Type canonicalization is sensitive to struct-ness

In some debug info of some shared library, the same type can be
present as a struct in some translation units, and as a class in
others.  As we are using the "pretty representation" of types to hash
types during type canonicalization, a "class foo" and "struct foo"
are (wrongly) considered different, because those pretty
representations are different.

This patch changes the canonicalization code to make it independent
from the struct-ness of the class being canonicalized.

	* include/abg-ir.h (class_decl::is_struct): Declare a setter for the
	"is-struct" property.
	* src/abg-ir.cc (class_decl::is_struct): And define that setter
	here.
	(type_base::get_canonical_type_for): Temporarily set the
	'is-struct' flag of the class type to 'false' before building its
	pretty representation.
	* tests/data/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so:
	New test input binary.
	* tests/data/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so.abi:
	New test reference output.
	* tests/data/Makefile.am: Add the new test material above to the
	source distribution.
	* tests/test-read-dwarf.cc (in_out_specs): Add the two new test
	inputs to the list of test inputs to consider.
	* tests/data/test-read-dwarf/test14-pr18893.so.abi: Adjust.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>

include/abg-ir.h

@@ -2816,6 +2816,9 @@ public:
   void
   set_is_declaration_only(bool f);
 
+  void
+  is_struct(bool f);
+
   bool
   is_struct() const;
 

src/abg-ir.cc

@@ -5854,21 +5854,40 @@ type_base::get_canonical_type_for(type_base_sptr t)
   environment* env = t->get_environment();
   assert(env);
 
+  class_decl_sptr is_class;
   // Look through declaration-only classes
   if (class_decl_sptr class_declaration = is_class_type(t))
-    if (class_declaration->get_is_declaration_only())
-      {
-	if (class_decl_sptr def =
-	    class_declaration->get_definition_of_declaration())
-	  t = def;
-	else
-	  return type_base_sptr();
-      }
+    {
+      if (class_declaration->get_is_declaration_only())
+	{
+	  if (class_decl_sptr def =
+	      class_declaration->get_definition_of_declaration())
+	    t = def;
+	  else
+	    return type_base_sptr();
+	}
+      is_class = is_class_type(t);
+    }
 
   if (t->get_canonical_type())
     return t->get_canonical_type();
 
+  bool is_struct = false;
+  if (is_class)
+    {
+      is_struct = is_class->is_struct();
+      // Make sure the struct-ness of the class doesn't influence the
+      // pretty representation that we are going to use for hashing
+      // purposes below.
+      is_class->is_struct(false);
+    }
+
   string repr = ir::get_pretty_representation(t);
+
+  if (is_class)
+    // Set the struct-ness of the class back.
+    is_class->is_struct(is_struct);
+
   environment::canonical_types_map_type& types =
     env->get_canonical_types_map();
 
@@ -10053,6 +10072,13 @@ void
 class_decl::set_is_declaration_only(bool f)
 {priv_->is_declaration_only_ = f;}
 
+/// Set the "is-struct" flag of the class.
+///
+/// @param f the new value of the flag.
+void
+class_decl::is_struct(bool f)
+{priv_->is_struct_ = f;}
+
 /// Test if the class is a struct.
 ///
 /// @return true iff the class is a struct.

tests/data/Makefile.am

@@ -296,6 +296,8 @@ test-read-dwarf/test17-pr19027.so \
 test-read-dwarf/test17-pr19027.so.abi \
 test-read-dwarf/test18-pr19037-libvtkRenderingLIC-6.1.so \
 test-read-dwarf/test18-pr19037-libvtkRenderingLIC-6.1.so.abi \
+test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so \
+test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so.abi \
 \
 test-diff-filter/test0-v0.cc		\
 test-diff-filter/test0-v1.cc		\

tests/test-read-dwarf.cc

@@ -146,6 +146,11 @@ InOutSpec in_out_specs[] =
     "data/test-read-dwarf/test18-pr19037-libvtkRenderingLIC-6.1.so.abi",
     "output/test-read-dwarf/test18-pr19037-libvtkRenderingLIC-6.1.so.abi",
   },
+  {
+    "data/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so",
+    "data/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so.abi",
+    "output/test-read-dwarf/test19-pr19023-libtcmalloc_and_profiler.so.abi",
+  },
   // This should be the last entry.
   {NULL, NULL, NULL}
 };