Fix PR68002, add -fkeep-static-functions

gcc/ChangeLog:

2015-10-17  Joost VandeVondele  <vondele@gnu.gcc.org>

        PR middle-end/68002
        * common.opt (fkeep-static-functions): New option.
        * doc/invoke.texi: Document it.
        * cgraphunit.c (cgraph_node::finalize_function): Use it.

gcc/testsuite/ChangeLog:

2015-10-17  Joost VandeVondele  <vondele@gnu.gcc.org>

        PR middle-end/68002
        * gcc.dg/PR68002.c: New test.

From-SVN: r228965

gcc/ChangeLog

+2015-10-19  Joost VandeVondele  <vondele@gnu.gcc.org>
+
+	PR middle-end/68002
+	* common.opt (fkeep-static-functions): New option.
+	* doc/invoke.texi: Document it.
+	* cgraphunit.c (cgraph_node::finalize_function): Use it.
+
 2015-10-19  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* sched-int.h (struct autopref_multipass_data_): Remove offset

gcc/cgraphunit.c

@@ -451,7 +451,7 @@ cgraph_node::finalize_function (tree decl, bool no_collect)
      declared inline and nested functions.  These were optimized out
      in the original implementation and it is unclear whether we want
      to change the behavior here.  */
-  if ((!opt_for_fn (decl, optimize)
+  if (((!opt_for_fn (decl, optimize) || flag_keep_static_functions)
        && !node->cpp_implicit_alias
        && !DECL_DISREGARD_INLINE_LIMITS (decl)
        && !DECL_DECLARED_INLINE_P (decl)

gcc/common.opt

@@ -1589,6 +1589,10 @@ fkeep-inline-functions
 Common Report Var(flag_keep_inline_functions)
 Generate code for functions even if they are fully inlined
 
+fkeep-static-functions
+Common Report Var(flag_keep_static_functions)
+Generate code for static functions even if they are never called 
+
 fkeep-static-consts
 Common Report Var(flag_keep_static_consts) Init(1)
 Emit static const variables even if they are not used

gcc/doc/invoke.texi

@@ -410,8 +410,8 @@ Objective-C and Objective-C++ Dialects}.
 -fira-loop-pressure -fno-ira-share-save-slots @gol
 -fno-ira-share-spill-slots -fira-verbose=@var{n} @gol
 -fisolate-erroneous-paths-dereference -fisolate-erroneous-paths-attribute @gol
--fivopts -fkeep-inline-functions -fkeep-static-consts @gol
--flive-range-shrinkage @gol
+-fivopts -fkeep-inline-functions -fkeep-static-functions @gol
+-fkeep-static-consts -flive-range-shrinkage @gol
 -floop-block -floop-interchange -floop-strip-mine @gol
 -floop-unroll-and-jam -floop-nest-optimize @gol
 -floop-parallelize-all -flra-remat -flto -flto-compression-level @gol
@@ -8013,6 +8013,11 @@ of its callers.  This switch does not affect functions using the
 @code{extern inline} extension in GNU C90@.  In C++, emit any and all
 inline functions into the object file.
 
+@item -fkeep-static-functions
+@optindex fkeep-static-functions
+Emit @code{static} functions into the object file, even if the function
+is never used.
+
 @item -fkeep-static-consts
 @opindex fkeep-static-consts
 Emit variables declared @code{static const} when optimization isn't turned

gcc/testsuite/ChangeLog

+2015-10-17  Joost VandeVondele  <vondele@gnu.gcc.org>
+
+	PR middle-end/68002
+	* gcc.dg/PR68002.c: New test.
+
 2015-10-19  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* gcc.dg/builtins-20.c: Remove undefined behavior.

gcc/testsuite/gcc.dg/PR68002.c

+/* Ensure static functions can be kept.  */
+/* { dg-do compile } */
+/* { dg-options "-O1 -fkeep-static-functions" } */
+
+static void bar () { }
+
+/* { dg-final { scan-assembler "bar" } } */