[llvm-commits] CVS: llvm-gcc/gcc/cp/class.c

[Chris Lattner]

Changes in directory llvm-gcc/gcc/cp:

class.c updated: 1.1.1.2 -> 1.2
---
Log message:

Fix PR602: http://llvm.cs.uiuc.edu/PR602  and Regression/C++Frontend/2005-07-21-VirtualBaseAccess.cpp, 
by forcing GCC to be more careful about the way it emits its unsafe pointer
casts.



---
Diffs of the changes:  (+15 -1)

 class.c |   16 +++++++++++++++-
 1 files changed, 15 insertions(+), 1 deletion(-)


Index: llvm-gcc/gcc/cp/class.c
diff -u llvm-gcc/gcc/cp/class.c:1.1.1.2 llvm-gcc/gcc/cp/class.c:1.2
--- llvm-gcc/gcc/cp/class.c:1.1.1.2	Tue Jan 13 10:49:36 2004
+++ llvm-gcc/gcc/cp/class.c	Thu Jul 21 16:56:03 2005
@@ -36,6 +36,7 @@
 #include "lex.h"
 #include "target.h"
 #include "convert.h"
+#include "llvm-out.h"
 
 /* The number of nested classes being processed.  If we are not in the
    scope of any class, this is zero.  */
@@ -356,12 +357,25 @@
   if (want_pointer)
     target_type = ptr_target_type;
   
-  expr = build1 (NOP_EXPR, ptr_target_type, expr);
+  /* To go from a derived class to a base member, do NOT first cast from
+   * derived* to base* then add an offset.  This sort of evil behavior results
+   * in invalid getelementptr instructions.
+   */
+#ifdef EMIT_LLVM
+  if (!integer_zerop (offset))
+    expr = build (code, ptr_target_type, expr, offset);
+  else
+    null_test = NULL;
 
+  expr = build1 (NOP_EXPR, ptr_target_type, expr);
+#else
+  expr = build1 (NOP_EXPR, ptr_target_type, expr);
+  
   if (!integer_zerop (offset))
     expr = build (code, ptr_target_type, expr, offset);
   else
     null_test = NULL;
+#endif  
   
   if (!want_pointer)
     expr = build_indirect_ref (expr, NULL);