[PATCH 09/14] ir: make "abidiff --debug-self-comparison vmlinux vmlinux" work

[Dodji Seketeli]

Today, "abidiff --debug-self-comparison vmlinux vmlinux" doesn't work
because homonym_type_group::get_canonical_type_for is designed for the
second argument to be an ABIXML file.

This patch adjusts that function to make it support the case of the
second binary being an ELF file and still detect erroneous cases where
the canonical type of a type originating from the second binary is
itself a type originating from the second binary.

	* src/abg-ir.cc (homonym_type_group::get_canonical_type_for): When
	--debug-self-comparison is used and when the two identical
	binaries are ELF binaries, detect erroneous cases where the
	canonical type of a type originating from the second binary is
	itself a type originating from the second binary.

Signed-off-by: Dodji Seketeli <dodji@seketeli.org>
---
 src/abg-ir.cc | 100 +++++++++++++++++++++++++++++---------------------
 1 file changed, 58 insertions(+), 42 deletions(-)

diff --git a/src/abg-ir.cc b/src/abg-ir.cc
index 8f43db58..a97e77cd 100644
--- a/src/abg-ir.cc
+++ b/src/abg-ir.cc
@@ -4086,25 +4086,27 @@ homonym_type_group::get_canonical_type_for(type_base_sptr t)
   if (env.self_comparison_debug_is_on())
     {
       // So we are debugging the canonicalization process,
-      // possibly via the use of 'abidw --debug-abidiff <binary>'.
+      // possibly via the use of 'abidw --debug-abidiff <binary>' or
+      // 'abidiff --debug-self-comparison <binary> <binary>'
       corpus_sptr corp1, corp2;
       env.get_self_comparison_debug_inputs(corp1, corp2);
-      if (corp1 && corp2 && type_originates_from_corpus(t, corp2)
-	  && corp1->get_origin() != corp2->get_origin()
-	  && corp2->get_origin() & corpus::NATIVE_XML_ORIGIN)
+      if (corp1 && corp2 && type_originates_from_corpus(t, corp2))
 	{
-	  // If 't' comes from the second corpus, then it *must*
-	  // be equal to its matching canonical type coming from
-	  // the first corpus because the second corpus is the
-	  // abixml representation of the first corpus.  In other
-	  // words, all types coming from the second corpus must
-	  // have canonical types coming from the first corpus.
+	  // If 't' comes from the second corpus, then it *must* be
+	  // equal to its matching canonical type coming from the
+	  // first corpus because the second corpus is equivalent to
+	  // the first corpus.  In other words, all types coming from
+	  // the second corpus must have canonical types coming from
+	  // the first corpus.
 	  if (result)
 	    {
-	      if (!env.priv_->
-		  check_canonical_type_from_abixml_during_self_comp(t,
-								    result))
+	      if ((corp1->get_origin() != corp2->get_origin()
+		   && (corp2->get_origin() & corpus::NATIVE_XML_ORIGIN))
+		  && !env.priv_->
+		  check_canonical_type_from_abixml_during_self_comp(t, result))
 		{
+		  // We must be in the case of 'abidw --debug-abidiff <binary>'
+		  //
 		  // The canonical type of the type re-read from abixml
 		  // type doesn't match the canonical type that was
 		  // initially serialized down.
@@ -4134,35 +4136,49 @@ homonym_type_group::get_canonical_type_for(type_base_sptr t)
 	    }
 	  else //!result
 	    {
-	      uintptr_t ptr_val = reinterpret_cast<uintptr_t>(t.get());
-	      string type_id = env.get_type_id_from_pointer(ptr_val);
-	      if (type_id.empty())
-		type_id = "type-id-<not-found>";
-	      // We are in the case where 't' is different from all
-	      // the canonical types of the same name that come from
-	      // the first corpus.
-	      //
-	      // If 't' indeed comes from the second corpus then this
-	      // clearly is a canonicalization failure.
-	      //
-	      // There was a problem either during the serialization
-	      // of 't' into abixml, or during the de-serialization
-	      // from abixml into abigail::ir.  Further debugging is
-	      // needed to determine what that root cause problem is.
-	      //
-	      // Note that the first canonicalization problem of this
-	      // kind must be fixed before looking at the subsequent
-	      // ones, because the later might well just be
-	      // consequences of the former.
-	      std::cerr << "error: wrong induced canonical type for '"
-			<< repr
-			<< "' from second corpus"
-			<< ", ptr: " << std::hex << t.get()
-			<< " type-id: " << type_id
-			<< " /hash="
-			<< *t->hash_value()
-			<< std::dec
-			<< std::endl;
+	      if (corp2->get_origin() & corpus::NATIVE_XML_ORIGIN)
+		{
+		  uintptr_t ptr_val = reinterpret_cast<uintptr_t>(t.get());
+		  string type_id = env.get_type_id_from_pointer(ptr_val);
+		  if (type_id.empty())
+		    type_id = "type-id-<not-found>";
+		  // We are in the case where 't' is different from all
+		  // the canonical types of the same name that come from
+		  // the first corpus.
+		  //
+		  // If 't' indeed comes from the second corpus then this
+		  // clearly is a canonicalization failure.
+		  //
+		  // There was a problem either during the serialization
+		  // of 't' into abixml, or during the de-serialization
+		  // from abixml into abigail::ir.  Further debugging is
+		  // needed to determine what that root cause problem is.
+		  //
+		  // Note that the first canonicalization problem of this
+		  // kind must be fixed before looking at the subsequent
+		  // ones, because the later might well just be
+		  // consequences of the former.
+		  std::cerr << "error: wrong induced canonical type for '"
+			    << repr
+			    << "' from second corpus"
+			    << ", ptr: " << std::hex << t.get()
+			    << " type-id: " << type_id
+			    << " /hash="
+			    << *t->hash_value()
+			    << std::dec
+			    << std::endl;
+		}
+	      else // The second corpus is not ABIXML
+		{
+		  std::cerr << "error: wrong induced canonical type for '"
+			    << repr
+			    << "' from second corpus"
+			    << ", ptr: " << std::hex << t.get()
+			    << " /hash="
+			    << *t->hash_value()
+			    << std::dec
+			    << std::endl;
+		}
 	    }
 	}
       if (result)
-- 
2.55.0