gimple.c (gimple_types_compatible_p): Return 0 for aggregate and pointer types if they have different alignment or mode.

	* gimple.c (gimple_types_compatible_p): Return 0 for aggregate and
	pointer types if they have different alignment or mode.

From-SVN: r159896

5 files changed, 51 insertions, 2 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a6da712..4769643 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2010-05-26  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gimple.c (gimple_types_compatible_p): Return 0 for aggregate and
+	pointer types if they have different alignment or mode.
+
 2010-05-26  Anatoly Sokolov  <aesok@post.ru>
 
 	* config/sparc/sparc.h (FUNCTION_VALUE, FUNCTION_OUTGOING_VALUE,
diff --git a/gcc/gimple.c b/gcc/gimple.c
index 07b91f8..759caf2 100644
--- a/gcc/gimple.c
+++ b/gcc/gimple.c
@@ -3299,8 +3299,7 @@ gimple_types_compatible_p (tree t1, tree t2)
   if (TREE_CODE (t1) == VOID_TYPE)
     return 1;
 
-  /* For numerical types do some simple checks before doing three
-     hashtable queries.  */
+  /* Do some simple checks before doing three hashtable queries.  */
   if (INTEGRAL_TYPE_P (t1)
       || SCALAR_FLOAT_TYPE_P (t1)
       || FIXED_POINT_TYPE_P (t1)
@@ -3334,6 +3333,14 @@ gimple_types_compatible_p (tree t1, tree t2)
       /* For integral types fall thru to more complex checks.  */
     }
 
+  else if (AGGREGATE_TYPE_P (t1) || POINTER_TYPE_P (t1))
+    {
+      /* Can't be the same type if they have different alignment or mode.  */
+      if (TYPE_ALIGN (t1) != TYPE_ALIGN (t2)
+	  || TYPE_MODE (t1) != TYPE_MODE (t2))
+	return 0;
+    }
+
   /* If the hash values of t1 and t2 are different the types can't
      possibly be the same.  This helps keeping the type-pair hashtable
      small, only tracking comparisons for hash collisions.  */
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8852b4a..d8a28db 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-05-26  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/lto10.adb: New test.
+	* gnat.dg/lto10_pkg.ads: New helper.
+
 2010-05-26  Kai Tietz  <kai.tietz@onevision.com>
 
 	* lib/target-supports.exp (check_effective_target_int128): New
diff --git a/gcc/testsuite/gnat.dg/lto10.adb b/gcc/testsuite/gnat.dg/lto10.adb
new file mode 100644
index 0000000..647ed00
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/lto10.adb
@@ -0,0 +1,14 @@
+-- { dg-do run }
+-- { dg-options "-flto" { target lto } }
+
+with Lto10_Pkg; use Lto10_Pkg;
+
+procedure Lto10 is
+   A : Integer := Minus_One;
+   Pos : Position;
+begin
+   Pos := Pix.Pos;
+   if A /= Minus_One then
+      raise Program_Error;
+   end if;
+end;
diff --git a/gcc/testsuite/gnat.dg/lto10_pkg.ads b/gcc/testsuite/gnat.dg/lto10_pkg.ads
new file mode 100644
index 0000000..9be6a78
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/lto10_pkg.ads
@@ -0,0 +1,18 @@
+package Lto10_Pkg is
+
+   type U16 is mod 2 ** 16;
+
+   type Position is record
+      X, Y, Z : U16;
+   end record;
+   for Position'Size use 48;
+
+   type Pixel is record
+      Pos : Position;
+   end record;
+   pragma Pack (Pixel);
+
+   Minus_One : Integer := -1;
+   Pix : Pixel := (Pos => (X => 0, Y => 0, Z => 0));
+
+end Lto10_Pkg;