add UNREACHABLE_RETURN

Not every compilers understand that rb_raise does not return.  When a
function does not end with a return statement, such compilers can issue
warnings.  We would better tell them about reachabilities.

1 files changed, 1 insertions, 0 deletions

diff --git a/process.c b/process.c
index a0b8467879..cd53030e9e 100644
--- a/process.c
+++ b/process.c
@@ -1900,6 +1900,7 @@ check_exec_redirect_fd(VALUE v, int iskey)
 
   wrong:
     rb_raise(rb_eArgError, "wrong exec redirect");
+    UNREACHABLE_RETURN(Qundef);
 }
 
 static VALUE