re PR sanitizer/78887 (Failure to build aarch64 allmodconfig Linux kernel 4.9)

	PR sanitizer/78887
	* asan.c (asan_needs_odr_indicator_p): Don't emit ODR indicators
	if -fsanitize=kernel-address is present.

From-SVN: r244402

gcc/ChangeLog

+2017-01-13  Maxim Ostapenko  <m.ostapenko@samsung.com>
+
+	PR sanitizer/78887
+	* asan.c (asan_needs_odr_indicator_p): Don't emit ODR indicators
+	if -fsanitize=kernel-address is present.
+
 2017-01-13  Richard Biener  <rguenther@suse.de>
 
 	* tree-pretty-print.c (dump_generic_node): Dump INTEGER_CSTs

gcc/asan.c

@@ -2360,7 +2360,16 @@ create_odr_indicator (tree decl, tree type)
 static bool
 asan_needs_odr_indicator_p (tree decl)
 {
-  return !DECL_ARTIFICIAL (decl) && !DECL_WEAK (decl) && TREE_PUBLIC (decl);
+  /* Don't emit ODR indicators for kernel because:
+     a) Kernel is written in C thus doesn't need ODR indicators.
+     b) Some kernel code may have assumptions about symbols containing specific
+        patterns in their names.  Since ODR indicators contain original names
+        of symbols they are emitted for, these assumptions would be broken for
+        ODR indicator symbols.  */
+  return (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS)
+	  && !DECL_ARTIFICIAL (decl)
+	  && !DECL_WEAK (decl)
+	  && TREE_PUBLIC (decl));
 }
 
 /* Append description of a single global DECL into vector V.