From: Georg-Johann Lay <avr@gjlay.de>
Date: Wed, 30 Nov 2016 11:08:37 +0000 (+0000)
Subject: re PR lto/78562 (Wrong warning for built-in functions with -flto)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6c8bf066581fe8bbd53e5967a49b6edd622f63b8;p=gcc.git

re PR lto/78562 (Wrong warning for built-in functions with -flto)

gcc/lto/
	PR lto/78562
	* lto-symtab.c (lto_symtab_merge_decls_2): Don't diagnose type
	mismatch if the two types are built-in.

From-SVN: r243008
---

diff --git a/gcc/lto/ChangeLog b/gcc/lto/ChangeLog
index 7957b2b7def..cf2248061c5 100644
--- a/gcc/lto/ChangeLog
+++ b/gcc/lto/ChangeLog
@@ -1,3 +1,9 @@
+2016-11-30  Georg-Johann Lay  <avr@gjlay.de>
+
+	PR lto/78562
+	* lto-symtab.c (lto_symtab_merge_decls_2): Don't diagnose type
+	mismatch if the two types are built-in.
+
 2016-11-26  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
 
 	* lto-lang.c (lto_init): Remove initialization of ptrdiff_type_node.
diff --git a/gcc/lto/lto-symtab.c b/gcc/lto/lto-symtab.c
index ce9e1465e3c..5ab9977ffea 100644
--- a/gcc/lto/lto-symtab.c
+++ b/gcc/lto/lto-symtab.c
@@ -655,6 +655,14 @@ lto_symtab_merge_decls_2 (symtab_node *first, bool diagnosed_p)
   /* Diagnose all mismatched re-declarations.  */
   FOR_EACH_VEC_ELT (mismatches, i, decl)
     {
+      /* Do not diagnose two built-in declarations, there is no useful
+         location in that case.  It also happens for AVR if two built-ins
+         use the same asm name because their libgcc assembler code is the
+         same, see PR78562.  */
+      if (DECL_IS_BUILTIN (prevailing->decl)
+	  && DECL_IS_BUILTIN (decl))
+	continue;
+
       int level = warn_type_compatibility_p (TREE_TYPE (prevailing->decl),
 					     TREE_TYPE (decl),
 					     DECL_COMDAT (decl));