Use strict function prototypes #945

`-Wstrict-prototypes` warn if a function is declared or defined without
specifying the argument types.

This warning disallow function prototypes with empty parameter list.
In C, a function declared with an empty parameter list accepts an
arbitrary number of arguments when being called. This is for historic
reasons; originally, C functions didn't have prototypes, as C evolved
from B, a typeless language. When prototypes were added, the original
typeless declarations were left in the language for backwards
compatibility.
Instead we should provide `void` in argument list to state
that function doesn't have arguments.

Also this warning disallow declaring type of the parameters after the
parentheses because Neovim header generator produce no declarations for
old-stlyle prototypes: it expects to find `{` after prototype.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/nvim/os/event.c b/src/nvim/os/event.c
index a9e97c9190..4e091716b2 100644
--- a/src/nvim/os/event.c
+++ b/src/nvim/os/event.c
@@ -33,7 +33,7 @@ typedef struct {
 #endif
 static klist_t(Event) *deferred_events, *immediate_events;
 
-void event_init()
+void event_init(void)
 {
   // Initialize the event queues
   deferred_events = kl_init(Event);
@@ -52,7 +52,7 @@ void event_init()
   server_init();
 }
 
-void event_teardown()
+void event_teardown(void)
 {
   channel_teardown();
   job_teardown();
@@ -122,7 +122,7 @@ bool event_poll(int32_t ms)
   return !timer_data.timed_out && (events_processed || event_has_deferred());
 }
 
-bool event_has_deferred()
+bool event_has_deferred(void)
 {
   return !kl_empty(get_queue(true));
 }