cse.c (cse_insn): Call never_reached_warning when a jump is changed to be unconditional.

* cse.c (cse_insn): Call never_reached_warning when a jump is
changed to be unconditional.
* flags.h: Declare warn_notreached.
* flow.c (delete_block): Call never_reached_warning when
a block is deleted.
* jump.c (delete_barrier_successors): Call never_reached_warning
when we delete everything after a BARRIER.
(never_reached_warning): New function.
* rtl.h: Declare never_reached_warning.
* toplev.c (warn_notreached): New variable.
(lang_independent_options): Set warn_notreached
when -Wunreachable-code.
(compile_file): We need line numbers for -Wunreachable-code.

Also modify documentation to suit.

From-SVN: r28747

1 files changed, 2 insertions, 0 deletions

diff --git a/gcc/cse.c b/gcc/cse.c
index 9eca723..f279cd1 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -7419,6 +7419,8 @@ cse_insn (insn, libcall_insn)
 	     not delete NOTEs except for NOTE_INSN_DELETED since later
 	     phases assume these notes are retained.  */
 
+	  never_reached_warning (insn);
+
 	  p = insn;
 
 	  while (NEXT_INSN (p) != 0