Conflict between Homie-esp8266 and DallasTemperature library

[philbarclay]

Compile success (using platformio) when using homie-esp8266 with the DallasTemperature library is dependant on the order of header file includes. If Homie.h comes first it compiles fine, if DallasTemperature.h it fails due to a conflict with the symbol/macro CONFIGURATION

This works:

#include <Homie.h>
#include <DallasTemperature.h>

void setup() { Homie.setup(); }
void loop() { Homie.loop(); }

This fails:

#include <DallasTemperature.h>
#include <Homie.h>

void setup() { Homie.setup(); }
void loop() { Homie.loop(); }

with output:

Compiling .pioenvs/esp12e/src/dep-testing.o
In file included from src/dep-testing.cpp:1:0:
.piolibdeps/DallasTemperature_ID54/DallasTemperature.h:44:25: error: expected identifier before numeric constant
#define CONFIGURATION   4
^
.piolibdeps/Homie/src/Homie/Datatypes/../../HomieBootMode.hpp:6:3: note: in expansion of macro 'CONFIGURATION'
CONFIGURATION = 2,
^

Compiled using platformio with config file:

[env:esp12e]
platform = espressif8266
board = esp12e
framework = arduino
lib_deps =
  DallasTemperature
  https://github.com/marvinroger/homie-esp8266.git#develop

Is this expected? I was under the impression the include order shouldn't matter?

[jamesmyatt]

I've already fixed this in the DallasTemperature library: https://github.com/milesburton/Arduino-Temperature-Control-Library/pull/75 You might need to use the git version though since I don't think it's released.

The problem was in that library using #define constants that are too general.

[philbarclay]

Confirmed. Changing to using the github version of DallasTemperature rather than whatever version platformio uses fixes this

This works with either order of includes:

[env:esp12e]
platform = espressif8266
board = esp12e
framework = arduino
lib_deps =
#  DallasTemperature
  https://github.com/milesburton/Arduino-Temperature-Control-Library.git
  https://github.com/marvinroger/homie-esp8266.git#develop