re PR ipa/65873 (Failure to inline always_inline memcpy)

	PR ipa/65873
	* ipa-inline.c (can_inline_edge_p): Allow early inlining of always
	inlines across optimization boundary.

From-SVN: r223107

gcc/ChangeLog

+2015-05-12  Jan Hubicka  <hubicka@ucw.cz>
+
+	PR ipa/65873
+	* ipa-inline.c (can_inline_edge_p): Allow early inlining of always
+	inlines across optimization boundary.
+
 2015-05-12  Jason Merrill  <jason@redhat.com>
 
 	* config/mmix/mmix.c, config/msp430/msp430.c: Add space between

gcc/ipa-inline.c

@@ -427,12 +427,20 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
 	      && lookup_attribute ("always_inline",
 				   DECL_ATTRIBUTES (callee->decl)));
 
+     /* Until GCC 4.9 we did not check the semantics alterning flags
+	bellow and inline across optimization boundry.
+	Enabling checks bellow breaks several packages by refusing
+	to inline library always_inline functions. See PR65873.
+	Disable the check for early inlining for now until better solution
+	is found.  */
+     if (always_inline && early)
+	;
       /* There are some options that change IL semantics which means
          we cannot inline in these cases for correctness reason.
 	 Not even for always_inline declared functions.  */
       /* Strictly speaking only when the callee contains signed integer
          math where overflow is undefined.  */
-      if ((check_maybe_up (flag_strict_overflow)
+     else if ((check_maybe_up (flag_strict_overflow)
 	       /* this flag is set by optimize.  Allow inlining across
 		  optimize boundary.  */
 	       && (!opt_for_fn (caller->decl, optimize)
@@ -449,9 +457,10 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
 	      || check_maybe_up (flag_signed_zeros)
 	      || check_maybe_down (flag_associative_math)
 	      || check_maybe_down (flag_reciprocal_math)
-	  /* We do not want to make code compiled with exceptions to be brought
-	     into a non-EH function unless we know that the callee does not
-	     throw.  This is tracked by DECL_FUNCTION_PERSONALITY.  */
+	      /* We do not want to make code compiled with exceptions to be
+		 brought into a non-EH function unless we know that the callee
+		 does not throw.
+		 This is tracked by DECL_FUNCTION_PERSONALITY.  */
 	      || (check_match (flag_non_call_exceptions)
 		  /* TODO: We also may allow bringing !flag_non_call_exceptions
 		     to flag_non_call_exceptions function, but that may need
@@ -481,6 +490,17 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
 	  e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
 	  inlinable = false;
 	}
+      /* If explicit optimize attribute are not used, the mismatch is caused
+	 by different command line options used to build different units.
+	 Do not care about COMDAT functions - those are intended to be
+         optimized with the optimization flags of module they are used in.
+	 Also do not care about mixing up size/speed optimization when
+	 DECL_DISREGARD_INLINE_LIMITS is set.  */
+      else if ((callee->merged
+	        && !lookup_attribute ("optimize",
+				      DECL_ATTRIBUTES (caller->decl)))
+	       || DECL_DISREGARD_INLINE_LIMITS (callee->decl))
+	;
       /* If mismatch is caused by merging two LTO units with different
 	 optimizationflags we want to be bit nicer.  However never inline
 	 if one of functions is not optimized at all.  */