This patch fixed google bug entry 6124850.
The usage of varpool_node has some restrictions on the corresponding var decl.
In LIPO mode function notice_global_symbol may call varpool_node with a decl
that doesn't satisfy these restrictions since the function notice_global_symbol
can be directly or indirectly called from anywhere. So we need to check if
a decl can be safely passed into varpoo_node before calling it.
Tested by ./buildit with targets x86-64 and power64 without regression.
OK for google branches?
thanks
Carrot
2013-05-09 Guozhi Wei <car...@google.com>
varasm.c (notice_global_symbol): Check conditions before calling
varpool_node.
Index: varasm.c
===================================================================
--- varasm.c (revision 198726)
+++ varasm.c (working copy)
@@ -1515,13 +1515,29 @@
|| !MEM_P (DECL_RTL (decl)))
return;
- if (L_IPO_COMP_MODE
- && ((TREE_CODE (decl) == FUNCTION_DECL
- && cgraph_is_auxiliary (decl))
- || (TREE_CODE (decl) == VAR_DECL
- && varpool_is_auxiliary (varpool_node (decl)))))
- return;
+ if (L_IPO_COMP_MODE)
+ {
+ if (TREE_CODE (decl) == FUNCTION_DECL && cgraph_is_auxiliary (decl))
+ return;
+ if (TREE_CODE (decl) == VAR_DECL)
+ {
+ /* Varpool_node can only accept var decl with flags
+ (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
+ For decl without these flags, we need to
+ check if it is auxiliary manually. */
+ if (!(TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
+ {
+ /* If a new varpool_node can be created,
+ the module id is current_module_id. */
+ if (current_module_id != primary_module_id)
+ return;
+ }
+ else if (varpool_is_auxiliary (varpool_node (decl)))
+ return;
+ }
+ }
+
/* We win when global object is found, but it is useful to know about weak
symbol as well so we can produce nicer unique names. */
if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
