ir: Arrays are indirect types for type structure similarity purposes

As described in the comments of types_have_similar_structure:

    "Two indirect types have similar structure if their underlying
    types are of the same kind and have the same name. [...] The size
    of their underlying type does not matter"

Yet, the size of array elements (a.k.a the underlying type of an array
type) is wrongly considered to matter when assessing the "type
structure similarity" relationship for arrays.

This patch fixes that.

	* src/abg-ir.cc (types_have_similar_structure): When examining
	array types, always treat element types as being underlying types
	of an indirect type.
	* tests/data/Makefile.am: Add new test case files.
	* tests/data/test-abidiff-exit/test-non-leaf-array-report.txt:
	New test case showing correct --leaf-changes-only reporting.
	* tests/data/test-abidiff-exit/test-non-leaf-array-v0.c:
	Likewise.
	* tests/data/test-abidiff-exit/test-non-leaf-array-v0.o:
	Likewise.
	* tests/data/test-abidiff-exit/test-non-leaf-array-v1.c:
	Likewise.
	* tests/data/test-abidiff-exit/test-non-leaf-array-v1.o:
	Likewise.
	* tests/test-abidiff-exit.cc: Run new test case.

Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Dodji Seketeli <dodji@redhat.com>

src/abg-ir.cc

@@ -23608,7 +23608,7 @@ types_have_similar_structure(const type_base* first,
 	  || ty1->get_dimension_count() != ty2->get_dimension_count()
 	  || !types_have_similar_structure(ty1->get_element_type(),
 					   ty2->get_element_type(),
-					   indirect_type))
+					   /*indirect_type=*/true))
 	return false;
 
       return true;

tests/data/Makefile.am

@@ -184,6 +184,11 @@ test-abidiff-exit/test-headers-dirs/test-headers-dir-v0.c \
 test-abidiff-exit/test-headers-dirs/test-headers-dir-v0.o \
 test-abidiff-exit/test-headers-dirs/test-headers-dir-v1.c \
 test-abidiff-exit/test-headers-dirs/test-headers-dir-v1.o \
+test-abidiff-exit/test-non-leaf-array-v0.c \
+test-abidiff-exit/test-non-leaf-array-v0.o \
+test-abidiff-exit/test-non-leaf-array-v1.c \
+test-abidiff-exit/test-non-leaf-array-v1.o \
+test-abidiff-exit/test-non-leaf-array-report.txt \
 \
 test-diff-dwarf/test0-v0.cc		\
 test-diff-dwarf/test0-v0.o			\

tests/data/test-abidiff-exit/test-non-leaf-array-report.txt

@@ -0,0 +1,11 @@
+Leaf changes summary: 1 artifact changed
+Changed leaf types summary: 1 leaf type changed
+Removed/Changed/Added functions summary: 0 Removed, 0 Changed, 0 Added function
+Removed/Changed/Added variables summary: 0 Removed, 0 Changed, 0 Added variable
+
+'struct buzz at test-non-leaf-array-v0.c:1:1' changed:
+  type size changed from 32 to 64 (in bits)
+  there are data member changes:
+    type 'int' of 'buzz::a' changed:
+      type name changed from 'int' to 'long int'
+      type size changed from 32 to 64 (in bits)

tests/data/test-abidiff-exit/test-non-leaf-array-v0.c

@@ -0,0 +1,12 @@
+struct buzz {
+  int a;
+};
+
+struct flexible {
+  long count;
+  struct buzz lightyear[0];
+};
+
+struct flexible var;
+void fun(struct flexible flex) { (void) flex; }
+

tests/data/test-abidiff-exit/test-non-leaf-array-v1.c

@@ -0,0 +1,12 @@
+struct buzz {
+  long a;
+};
+
+struct flexible {
+  long count;
+  struct buzz lightyear[0];
+};
+
+struct flexible var;
+void fun(struct flexible flex) { (void) flex; }
+

tests/test-abidiff-exit.cc

@@ -337,6 +337,17 @@ InOutSpec in_out_specs[] =
     "data/test-abidiff-exit/test-headers-dirs/test-headers-dir-report-2.txt",
     "output/test-abidiff-exit/test-headers-dirs/test-headers-dir-report-2.txt"
   },
+  {
+    "data/test-abidiff-exit/test-non-leaf-array-v0.o",
+    "data/test-abidiff-exit/test-non-leaf-array-v1.o",
+    "",
+    "",
+    "",
+    "--leaf-changes-only",
+    abigail::tools_utils::ABIDIFF_ABI_CHANGE,
+    "data/test-abidiff-exit/test-non-leaf-array-report.txt",
+    "output/test-abidiff-exit/test-non-leaf-array-report.txt"
+  },
   {0, 0, 0 ,0, 0, 0, abigail::tools_utils::ABIDIFF_OK, 0, 0}
 };