decl.c (gnat_to_gnu_param): Do not strip the padding if the parameter either is passed by reference or if...

	* gcc-interface/decl.c (gnat_to_gnu_param): Do not strip the padding
	if the parameter either is passed by reference or if the alignment
	would be lowered.

From-SVN: r220514

7 files changed, 57 insertions, 4 deletions

diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 59c6c38..874779e 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,5 +1,11 @@
 2015-02-08  Eric Botcazou  <ebotcazou@adacore.com>
 
+	* gcc-interface/decl.c (gnat_to_gnu_param): Do not strip the padding
+	if the parameter either is passed by reference or if the alignment
+	would be lowered.
+
+2015-02-08  Eric Botcazou  <ebotcazou@adacore.com>
+
 	* gcc-interface/decl.c (is_cplusplus_method): Use Is_Primitive flag to
 	detect primitive operations of tagged and untagged types.
 
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c
index c7d64aa..94043b6 100644
--- a/gcc/ada/gcc-interface/decl.c
+++ b/gcc/ada/gcc-interface/decl.c
@@ -5659,15 +5659,17 @@ gnat_to_gnu_param (Entity_Id gnat_param, Mechanism_Type mech,
     }
 
   /* If this is either a foreign function or if the underlying type won't
-     be passed by reference, strip off possible padding type.  */
+     be passed by reference and is as aligned as the original type, strip
+     off possible padding type.  */
   if (TYPE_IS_PADDING_P (gnu_param_type))
     {
       tree unpadded_type = TREE_TYPE (TYPE_FIELDS (gnu_param_type));
 
-      if (mech == By_Reference
-	  || foreign
+      if (foreign
 	  || (!must_pass_by_ref (unpadded_type)
-	      && (mech == By_Copy || !default_pass_by_ref (unpadded_type))))
+	      && mech != By_Reference
+	      && (mech == By_Copy || !default_pass_by_ref (unpadded_type))
+	      && TYPE_ALIGN (unpadded_type) >= TYPE_ALIGN (gnu_param_type)))
 	gnu_param_type = unpadded_type;
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index dbe52cf..8783389 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-08  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/addr7.ad[sb]: New test.
+	* gnat.dg/addr8.ad[sb]: Likewise.
+
 2015-02-06  David Malcolm  <dmalcolm@redhat.com>
 
 	PR jit/64752
diff --git a/gcc/testsuite/gnat.dg/addr7.adb b/gcc/testsuite/gnat.dg/addr7.adb
new file mode 100644
index 0000000..982b50e
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/addr7.adb
@@ -0,0 +1,12 @@
+-- { dg-do compile }
+
+package body Addr7 is
+
+   procedure Proc (B: aliased Bytes) is
+      O: Integer;
+      for O'Address use B'Address;
+   begin
+      null;
+   end;
+
+end Addr7;
diff --git a/gcc/testsuite/gnat.dg/addr7.ads b/gcc/testsuite/gnat.dg/addr7.ads
new file mode 100644
index 0000000..19fbb0e
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/addr7.ads
@@ -0,0 +1,8 @@
+package Addr7 is
+
+   type Bytes is array (1 .. 4) of Character;
+   for Bytes'Alignment use 4;
+
+   procedure Proc (B: aliased Bytes);
+
+end Addr7;
diff --git a/gcc/testsuite/gnat.dg/addr8.adb b/gcc/testsuite/gnat.dg/addr8.adb
new file mode 100644
index 0000000..9105c22f
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/addr8.adb
@@ -0,0 +1,12 @@
+-- { dg-do compile }
+
+package body Addr8 is
+
+   procedure Proc (B: Bytes) is
+      O: Integer;
+      for O'Address use B'Address;
+   begin
+      null;
+   end;
+
+end Addr8;
diff --git a/gcc/testsuite/gnat.dg/addr8.ads b/gcc/testsuite/gnat.dg/addr8.ads
new file mode 100644
index 0000000..ab648e1
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/addr8.ads
@@ -0,0 +1,8 @@
+package Addr8 is
+
+   type Bytes is array (1 .. 4) of Character;
+   for Bytes'Alignment use 4;
+
+   procedure Proc (B: Bytes);
+
+end Addr8;