synchronized with lua-nginx-module #2a19073 (remove error logging on coroutine runtime errors).

Author: thibaultcha

src/subsys/ngx_subsys_lua_util.c.tt2

@@ -1092,6 +1092,14 @@ ngx_[% subsys %]_lua_run_thread(lua_State *L, [% req_type %] *r,
 
     NGX_LUA_EXCEPTION_TRY {
 
+        /*
+         * silence a -Werror=clobbered warning with gcc 5.4
+         * due to above setjmp
+         */
+        err = NULL;
+        msg = NULL;
+        trace = NULL;
+
         if (ctx->cur_co_ctx->thread_spawn_yielded) {
             ngx_[% subsys %]_lua_probe_info("thread spawn yielded");
 
@@ -1464,30 +1472,34 @@ user_co_done:
                 ctx->cur_co_ctx = orig_coctx;
             }
 
-            if (lua_isstring(ctx->cur_co_ctx->co, -1)) {
-                dd("user custom error msg");
-                msg = lua_tostring(ctx->cur_co_ctx->co, -1);
-
-            } else {
-                msg = "unknown reason";
-            }
-
             ngx_[% subsys %]_lua_cleanup_pending_operation(ctx->cur_co_ctx);
 
             ngx_[% subsys %]_lua_probe_coroutine_done(r, ctx->cur_co_ctx->co, 0);
 
             ctx->cur_co_ctx->co_status = NGX_[% SUBSYS %]_LUA_CO_DEAD;
 
-            ngx_[% subsys %]_lua_thread_traceback(L, ctx->cur_co_ctx->co,
-                                                  ctx->cur_co_ctx);
-            trace = lua_tostring(L, -1);
+            if (orig_coctx->is_uthread
+                || orig_coctx->is_wrap
+                || ngx_[% subsys %]_lua_is_entry_thread(ctx))
+            {
+                ngx_[% subsys %]_lua_thread_traceback(L, orig_coctx->co,
+                                                      orig_coctx);
+                trace = lua_tostring(L, -1);
+
+                if (lua_isstring(orig_coctx->co, -1)) {
+                    msg = lua_tostring(orig_coctx->co, -1);
+                    dd("user custom error msg: %s", msg);
 
-propagate_error:
+                } else {
+                    msg = "unknown reason";
+                }
+            }
 
-            ngx_[% subsys %]_lua_assert(err != NULL && msg != NULL
-                                        && trace != NULL);
+propagate_error:
 
             if (ctx->cur_co_ctx->is_uthread) {
+                ngx_[% subsys %]_lua_assert(err != NULL && msg != NULL
+                                            && trace != NULL);
 
                 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                               "[% log_prefix %]lua user thread aborted: %s: %s\n%s",
@@ -1538,6 +1550,9 @@ propagate_error:
             }
 
             if (ngx_[% subsys %]_lua_is_entry_thread(ctx)) {
+                ngx_[% subsys %]_lua_assert(err != NULL && msg != NULL
+                                            && trace != NULL);
+
                 ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                               "lua entry thread aborted: %s: %s\n%s",
                               err, msg, trace);
@@ -1603,9 +1618,6 @@ propagate_error:
             lua_xmove(orig_coctx->co, next_co, 1);
             nrets = 2;
 
-            ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                          "lua coroutine: %s: %s\n%s", err, msg, trace);
-
             /* try resuming on the new coroutine again */
             continue;
         }