273     failf(conn->data, "Failed sending HTTP2 data");  in send_callback()
395       failf(data, "Internal NULL stream!\n");  in push_promise()
821     failf(data_s, "Internal NULL stream! 5\n");  in on_header()
998       failf(conn->data, "Couldn't initialize nghttp2 callbacks!");  in Curl_http2_init()
1039       failf(conn->data, "Couldn't initialize nghttp2!");  in Curl_http2_init()
1069     failf(conn->data, "nghttp2 unexpectedly failed on pack_settings_payload");  in Curl_http2_request_upgrade()
1120     failf(data,  in h2_process_pending_input()
1185     failf(data, "HTTP/2 stream %u was not closed cleanly: %s (err %d)",  in http2_handle_stream_close()
1193     failf(data, "HTTP/2 stream %u was closed cleanly, but before getting "  in http2_handle_stream_close()
1402           failf(data, "Failed receiving HTTP2 data");  in http2_recv()
1412         failf(data, "Unexpected EOF");  in http2_recv()
1432       failf(data, "nghttp2_session_mem_recv() returned %d:%s\n",  in http2_recv()
1600     failf(conn->data, "Failed sending HTTP request: Header overflow");  in http2_send()
1622     failf(conn->data, "Failed sending HTTP request: Header overflow");  in http2_send()
1638     failf(conn->data, "Failed sending HTTP request: Header overflow");  in http2_send()
1687         failf(conn->data, "Failed sending HTTP request: Header overflow");  in http2_send()
1886       failf(data, "nghttp2_session_upgrade() failed: %s(%d)",  in Curl_http2_switched()
1900       failf(data, "nghttp2_submit_settings() failed: %s(%d)",  in Curl_http2_switched()
1911     failf(data, "connection buffer size is too small to store data following "  in Curl_http2_switched()
1928     failf(data, "nghttp2_session_mem_recv() failed: %s(%d)",  in Curl_http2_switched()
1947     failf(data, "nghttp2_session_send() failed: %s(%d)",  in Curl_http2_switched()