[PATCH] Do not declare artificial variables in tree-profile.c to have a definition (PR lto/69188).

[Martin Liška]

Hello.

Nice example provided in the PR causes ICE as we have an artificial symbol
created in tree-profile.c once being removed by remove unreachable nodes (-O0)
and once not (-O1). Well, difference is in process_references where following 
hunk
prevent removal:

              || (((before_inlining_p
                    && ((TREE_CODE (node->decl) != FUNCTION_DECL
                         && optimize)

Anyway, these artificial symbols really should be just declarations as they are 
defined
in libgcov library.

Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.

Ready to be installed?
Martin

>From 87262b1b60009381fd943fb433bc38f5d5685ac9 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Fri, 13 Jan 2017 13:12:57 +0100
Subject: [PATCH] Do not declare artificial variables in tree-profile.c to have
 a definition (PR lto/69188).

gcc/testsuite/ChangeLog:

2017-01-13  Martin Liska  <mli...@suse.cz>

	PR lto/69188
	* gcc.dg/lto/pr69188_0.c: New test.
	* gcc.dg/lto/pr69188_1.c: New test.

gcc/ChangeLog:

2017-01-13  Martin Liska  <mli...@suse.cz>

	PR lto/69188
	* tree-profile.c (init_ic_make_global_vars): Do not call
	finalize_decl.
	(gimple_init_gcov_profiler): Likewise.
---
 gcc/testsuite/gcc.dg/lto/pr69188_0.c |  7 +++++++
 gcc/testsuite/gcc.dg/lto/pr69188_1.c | 10 ++++++++++
 gcc/tree-profile.c                   |  6 ------
 3 files changed, 17 insertions(+), 6 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/lto/pr69188_0.c
 create mode 100644 gcc/testsuite/gcc.dg/lto/pr69188_1.c

diff --git a/gcc/testsuite/gcc.dg/lto/pr69188_0.c b/gcc/testsuite/gcc.dg/lto/pr69188_0.c
new file mode 100644
index 00000000000..8bee874a65b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr69188_0.c
@@ -0,0 +1,7 @@
+/* PR ipa/69188 */
+/* { dg-lto-do link } */
+/* { dg-lto-options { { -flto -O0 -fprofile-generate } } } */
+
+void fn1(void) 
+{ 
+}
diff --git a/gcc/testsuite/gcc.dg/lto/pr69188_1.c b/gcc/testsuite/gcc.dg/lto/pr69188_1.c
new file mode 100644
index 00000000000..3ed9d5560c6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr69188_1.c
@@ -0,0 +1,10 @@
+/* PR ipa/69188 */
+/* { dg-options "-flto -O1 -fprofile-generate" } */
+
+extern void fn1(void);
+
+int main() {
+  fn1();
+  return 0;
+}
+
diff --git a/gcc/tree-profile.c b/gcc/tree-profile.c
index 186cfdf7929..a49ec37f8bb 100644
--- a/gcc/tree-profile.c
+++ b/gcc/tree-profile.c
@@ -94,8 +94,6 @@ init_ic_make_global_vars (void)
   if (targetm.have_tls)
     set_decl_tls_model (ic_void_ptr_var, decl_default_tls_model (ic_void_ptr_var));
 
-  varpool_node::finalize_decl (ic_void_ptr_var);
-
   gcov_type_ptr = build_pointer_type (get_gcov_type ());
 
   ic_gcov_type_ptr_var
@@ -112,8 +110,6 @@ init_ic_make_global_vars (void)
   DECL_INITIAL (ic_gcov_type_ptr_var) = NULL;
   if (targetm.have_tls)
     set_decl_tls_model (ic_gcov_type_ptr_var, decl_default_tls_model (ic_gcov_type_ptr_var));
-
-  varpool_node::finalize_decl (ic_gcov_type_ptr_var);
 }
 
 /* Create the type and function decls for the interface with gcov.  */
@@ -210,8 +206,6 @@ gimple_init_gcov_profiler (void)
       DECL_ARTIFICIAL (tree_time_profiler_counter) = 1;
       DECL_INITIAL (tree_time_profiler_counter) = NULL;
 
-      varpool_node::finalize_decl (tree_time_profiler_counter);
-
       /* void (*) (gcov_type *, gcov_type)  */
       average_profiler_fn_type
 	      = build_function_type_list (void_type_node,
-- 
2.11.0