ESP8266WebServer hangs after updating to 2.5.0 · Issue #5736 · esp8266/Arduino (original) (raw)

Basic Infos

• This issue complies with the issue POLICY doc.
• I have read the documentation at readthedocs and the issue is not addressed there.
• I have tested that the issue is present in current master branch (aka latest git).
• I have searched the issue tracker for a similar issue.
• If there is a stack dump, I have decoded it.
• I have filled out all fields below.

Platform

• Hardware: ESP8266
• Core Version: 2.5.0
• Development Env: Arduino IDE
• Operating System: MacOS

Settings in IDE

• Module: NodeMCU1.0
• Flash Mode: n/a
• Flash Size: 4MB/3MB
• lwip Variant: v2 Lower Memory
• Reset Method: n/a
• Flash Frequency: n/a
• CPU Frequency: 80Mhz
• Upload Using: SERIAL
• Upload Speed: 115200

Problem Description

After updating to v2.5.0 my sketch can't get a reliable connection to the ESP8266WebServer server. Trying to connect to the ESP from a browser succeeds occasionally, but most of the time the browser hangs and eventually gives up.

I loaded the simple HelloServer example sketch that comes with ESP8266WebServer and it does the same thing. The browser just sits there. Tried various lwIP variants, but none helped. Oddly, turning on all debug options made the problem happen less often.

It seems related to issue #5725, although for me ping requests constantly timeout.

Revert back to v2.4.2 and the problem goes away.

MCVE Sketch

Use the HelloServer example sketch provided with ESP8266WebServer.

Debug Messages

Problem goes away (or at least gets much better) when all debug options are enabled.