From: Eric Botcazou <ebotcazou@adacore.com>
Date: Thu, 7 Sep 2023 08:53:39 +0000 (+0200)
Subject: ada: Fix internal error on misaligned component with variable nominal size
X-Git-Tag: basepoints/gcc-15~6111
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=140e20f69754bd04b7ee47518d065c1338780c36;p=thirdparty%2Fgcc.git

ada: Fix internal error on misaligned component with variable nominal size

The back-end cannot handle this kind of components even when they are small.

gcc/ada/

	* exp_util.adb (Component_May_Be_Bit_Aligned): Do not return false
	for a small component of a record type with a variant part.
---

diff --git a/gcc/ada/exp_util.adb b/gcc/ada/exp_util.adb
index b2542d4ae593..2e6a1cf892eb 100644
--- a/gcc/ada/exp_util.adb
+++ b/gcc/ada/exp_util.adb
@@ -4989,12 +4989,15 @@ package body Exp_Util is
          return False;
 
       --  If we know that we have a small (at most the maximum integer size)
-      --  record or bit-packed array, then everything is fine, since the back
-      --  end can handle these cases correctly, except if a slice is involved.
+      --  bit-packed array or record without variant part, then everything is
+      --  fine, since the back end can handle these cases correctly, except if
+      --  a slice is involved.
 
       elsif Known_Esize (Comp)
         and then Esize (Comp) <= System_Max_Integer_Size
-        and then (Is_Record_Type (UT) or else Is_Bit_Packed_Array (UT))
+        and then (Is_Bit_Packed_Array (UT)
+                   or else (Is_Record_Type (UT)
+                             and then not Has_Variant_Part (UT)))
         and then not For_Slice
       then
          return False;