File static data member changes in STATIC_DATA_MEMBER_CHANGE_CATEGORY

* include/abg-comparison.h
	(diff_category::STATIC_DATA_MEMBER_CHANGE_CATEGORY): New category.
	(diff_category::EVERYTHING_CATEGORY): Update
	* src/abg-comp-filter.cc (static_data_member_type_size_changed)
	(static_data_member_added_or_removed): Define new static
	functions.
	(harmless_filter::visit): Categorize changes to static data
	members as STATIC_DATA_MEMBER_CHANGE_CATEGORY.
	* tools/bidiff.cc (set_diff_context_from_opts):
	STATIC_DATA_MEMBER_CHANGE_CATEGORY is falls into the harmless
	group.
	* tests/data/test-diff-filter/test12-report.txt: New test input.
	* tests/data/test-diff-filter/test12-v0.cc: Likewise.
	* tests/data/test-diff-filter/test12-v0.o: Likewise.
	* tests/data/test-diff-filter/test12-v1.cc: Likewise.
	* tests/data/test-diff-filter/test12-v1.o: Likewise.
	* tools/bidiff.cc: Run this test with the additional input data
	above.
	* tests/Makefile.am: Adjust.

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

include/abg-comparison.h

@@ -245,15 +245,18 @@ enum diff_category
   /// or removal of a non-virtual member function.
   NON_VIRT_MEM_FUN_CHANGE_CATEGORY = 1 << 3,
 
+  /// This means that a diff node in the sub-tree carries an addition
+  /// or removal of a static data member.
+  STATIC_DATA_MEMBER_CHANGE_CATEGORY = 1 << 4,
 
   /// This means the diff node (or at least one of its descendant
   /// nodes) carries a change that modifies the size of a type or an
   /// offset of a type member.
-  SIZE_OR_OFFSET_CHANGE_CATEGORY = 1 << 4,
+  SIZE_OR_OFFSET_CHANGE_CATEGORY = 1 << 5,
 
   /// This means that a diff node in the sub-tree carries a change to
   /// a vtable.
-  VIRTUAL_MEMBER_CHANGE_CATEGORY = 1 << 5,
+  VIRTUAL_MEMBER_CHANGE_CATEGORY = 1 << 6,
 
   /// A special enumerator that is the logical 'or' all the
   /// enumerators above.
@@ -265,6 +268,7 @@ enum diff_category
   | COMPATIBLE_TYPE_CHANGE_CATEGORY
   | DECL_NAME_CHANGE_CATEGORY
   | NON_VIRT_MEM_FUN_CHANGE_CATEGORY
+  | STATIC_DATA_MEMBER_CHANGE_CATEGORY
   | SIZE_OR_OFFSET_CHANGE_CATEGORY
   | VIRTUAL_MEMBER_CHANGE_CATEGORY
 };

src/abg-comp-filter.cc

@@ -200,6 +200,30 @@ non_static_data_member_type_size_changed(decl_base_sptr f, decl_base_sptr s)
   return type_size_changed(fv->get_type(), sv->get_type());
 }
 
+/// Test if the size of a non-static data member changed accross two
+/// versions.
+///
+/// @param f the first version of the non-static data member.
+///
+/// @param s the second version of the non-static data member.
+static bool
+static_data_member_type_size_changed(decl_base_sptr f, decl_base_sptr s)
+{
+  if (!is_member_decl(f)
+      || !is_member_decl(s))
+    return false;
+
+  var_decl_sptr fv = dynamic_pointer_cast<var_decl>(f),
+    sv = dynamic_pointer_cast<var_decl>(s);
+  if (!fv
+      || !sv
+      || !get_member_is_static(fv)
+      || !get_member_is_static(sv))
+    return false;
+
+  return type_size_changed(fv->get_type(), sv->get_type());
+}
+
 /// Test if two types are different but compatible.
 ///
 /// @param d1 the declaration of the first type to consider.
@@ -279,6 +303,49 @@ non_static_data_member_added_or_removed(const diff* diff)
     (dynamic_cast<const class_diff*>(diff));
 }
 
+/// Test if a class_diff node has static members added or removed.
+///
+/// @param diff the diff node to consider.
+///
+/// @return true iff the class_diff node has static members added
+/// or removed.
+static bool
+static_data_member_added_or_removed(const class_diff* diff)
+{
+  if (diff && !diff_involves_decl_only_class(diff))
+    {
+      for (string_decl_base_sptr_map::const_iterator i =
+	     diff->inserted_data_members().begin();
+	   i != diff->inserted_data_members().end();
+	   ++i)
+	if (get_member_is_static(i->second))
+	  return true;
+
+      for (string_decl_base_sptr_map::const_iterator i =
+	     diff->deleted_data_members().begin();
+	   i != diff->deleted_data_members().end();
+	   ++i)
+	if (get_member_is_static(i->second))
+	  return true;
+    }
+
+  return false;
+}
+
+/// Test if a class_diff node has static members added or
+/// removed.
+///
+/// @param diff the diff node to consider.
+///
+/// @return true iff the class_diff node has static members added
+/// or removed.
+static bool
+static_data_member_added_or_removed(const diff* diff)
+{
+  return static_data_member_added_or_removed
+    (dynamic_cast<const class_diff*>(diff));
+}
+
 /// Test if the class_diff node has a change involving virtual member
 /// functions.
 ///
@@ -448,6 +515,10 @@ harmless_filter::visit(diff* d, bool pre)
       if (has_non_virtual_mem_fn_change(d))
 	category |= NON_VIRT_MEM_FUN_CHANGE_CATEGORY;
 
+      if (static_data_member_added_or_removed(d)
+	  || static_data_member_type_size_changed(f, s))
+	category |= STATIC_DATA_MEMBER_CHANGE_CATEGORY;
+
       if (category)
 	d->add_to_category(category);
     }

tests/Makefile.am

@@ -219,7 +219,12 @@ data/test-diff-filter/test11-v0.cc		\
 data/test-diff-filter/test11-v1.cc		\
 data/test-diff-filter/test11-v0.o		\
 data/test-diff-filter/test11-v1.o		\
-data/test-diff-filter/test11-report.txt
+data/test-diff-filter/test11-report.txt		\
+data/test-diff-filter/test12-v0.cc		\
+data/test-diff-filter/test12-v1.cc		\
+data/test-diff-filter/test12-v0.o		\
+data/test-diff-filter/test12-v1.o		\
+data/test-diff-filter/test12-report.txt
 
 clean-local: clean-local-check
 .PHONY: clean-local-check

tests/data/test-diff-filter/test12-report.txt

@@ -0,0 +1,7 @@
+Functions changes summary: 0 Removed, 0 Changed (1 filtered out), 0 Added function
+Variables changes summary: 0 Removed, 0 Changed, 1 Added variable
+
+
+1 Added variable:
+  'static char S::m0
+

tests/data/test-diff-filter/test12-v0.cc

@@ -0,0 +1,10 @@
+struct S
+{
+  static int m1;
+};
+
+int S::m1;
+
+void
+foo(S&)
+{}

tests/data/test-diff-filter/test12-v1.cc

@@ -0,0 +1,12 @@
+struct S
+{
+  static char m0;
+  static int m1;
+};
+
+char S::m0;
+int S::m1;
+
+void
+foo(S&)
+{}

tests/test-diff-filter.cc

@@ -145,6 +145,13 @@ InOutSpec in_out_specs[] =
     "data/test-diff-filter/test11-report.txt",
     "output/test-diff-filter/test11-report.txt",
   },
+  {
+    "data/test-diff-filter/test12-v0.o",
+    "data/test-diff-filter/test12-v1.o",
+    "--no-harmless",
+    "data/test-diff-filter/test12-report.txt",
+    "output/test-diff-filter/test12-report.txt",
+  },
   // This should be the last entry
   {NULL, NULL, NULL, NULL, NULL}
 };

tools/bidiff.cc

@@ -297,7 +297,8 @@ set_diff_context_from_opts(diff_context_sptr ctxt,
 	(abigail::comparison::ACCESS_CHANGE_CATEGORY
 	 | abigail::comparison::COMPATIBLE_TYPE_CHANGE_CATEGORY
 	 | abigail::comparison::DECL_NAME_CHANGE_CATEGORY
-	 | abigail::comparison::NON_VIRT_MEM_FUN_CHANGE_CATEGORY);
+	 | abigail::comparison::NON_VIRT_MEM_FUN_CHANGE_CATEGORY
+	 | abigail::comparison::STATIC_DATA_MEMBER_CHANGE_CATEGORY);
   if (!opts.show_harmful_changes)
     ctxt->switch_categories_off
       (abigail::comparison::SIZE_OR_OFFSET_CHANGE_CATEGORY