Qt Conan package troubleshooting

Here you can find causes for commonly encountered issues with Conan

• *** No rule to make target 'hdb', needed by 'all-local'.
  • When compiling Qt from sources (qtbase more specifically) and you have enabled ICU (e.g. qtbase:icu=True in the --profile used) the build recipe of the ICU attempts to read 'TARGET' environment variable and if that happens to contain a value the ICU recipe does not accept it will throw an error:

    errors: logfile attached
    make[1]: *** No rule to make target 'hdb', needed by 'all-local'. Stop.
    make: *** [Makefile:143: all-recursive] Error
    ERROR: icu/56.1@qt/everywhere: Error in build() method, line 156
    

  • Fix:
    • $ unset TARGET
      
• Connection issues with the default conan-center remote (not hosted by Qt)
  • Unable to connect to conancenter=https://center.conan.io
  • ERROR: HTTPSConnectionPool(host='center.conan.io', port=443): Max retries exceeded with url: /v1/ping (Caused by ResponseError('too many 502 error responses')). [Remote: conancenter]
  • Fix:
    • If you do not need any packages from the conan-center you can disable it temporarily by: $ conan remote disable conancenter
• ERROR: Missing prebuilt package for ....
  • Qt provides pre-built binaries for release build configurations. Those build configurations are available as the build profiles which are also provided per released Qt version. An easy way to access the build profiles is installing "qtbuildprofiles/<version>@qt/everywhere" package.
  • If the settings or options differ from those used for the official Qt release builds then Conan can not find a matching pre-built binary from the server thus the error message given.
    • Fix:
      • If you need the pre-built binaries then use the build profiles that were used to produce the release Conan packages
      • If you need a custom configuration then you can ask Conan to build it for you from sources:
        • $ conan install <package> --build=missing ..."