FPSTR not portable between ESP8266 and ESP32 #7940
Description
Board
ESP32 Dev Module
Device Description
DevKitC
Version
latest master (checkout manually)
IDE Name
Arduino IDE
Operating System
Windows 10
Description
After all these years, the following MCVE still does not compile without changes on both ESP8266 Core master and ESP32 Core master.
Shouldn't FPSTR correctly be defined as a noop on ESP32 instead of ... __FlashStringHelper ...?
Sketch
#if defined(ESP8266) #include <ESP8266mDNS.h> #elif defined(ESP32) #include <ESPmDNS.h> #endif static const char MDNSNAME[] PROGMEM = "esp"; // your device's MDNS host name void setup() { MDNS.begin(FPSTR(MDNSNAME)); } void loop() { }Debug Message
Compiling on ESP8266 works, on ESP32 fails:
fpstr_issue.ino: In function void setup() fpstr_issue.ino: 11:31: error: no matching function for call to 'MDNSResponder::begin(const __FlashStringHelper*) MDNS.begin(FPSTR(MDNSNAME)) fpstr_issue.ino:4: In file included from ESPmDNS.h:57: note candidate bool MDNSResponder begin(const char*) bool begin(const char* hostName) ^~~~~ ESPmDNS.h:57: note no known conversion for argument 1 from const __FlashStringHelper* to const char* Error compiling project sources Build failed for project 'fpstr_issue' ### I have checked existing issues, online documentation and the Troubleshooting Guide - [X] I confirm I have checked existing issues, online documentation and Troubleshooting guide.