GeographicLib cmake file in wrong place

[Ian Vaughn]

The geographiclib-dev installer puts the FindGeographicLib.cmake file in:
/usr/share/cmake/geographiclib/FindGeographicLib.cmake

The correct location is:
/usr/share/cmake-3.5/Modules

The first location is not in the cmake path, so it never gets found by cmake and is more or less completely useless by default. The file itself seems fine once I add it to the cmake path, so it looks like a simple install script bug.

This bug was originally discovered with libgeographiclib-dev 1.45-2 in xenial, but it appears to still be present in package 1.49 in bionic.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Ian Colwell (iancol)]

Somewhat related issue as well:
https://stackoverflow.com/a/48524106/8008576

[Martin Pecka (peci1)]

Workaround for downstream projects:

set(CMAKE_MODULE_PATH "${CMAKE_MODULE_PATH};/usr/share/cmake/geographiclib")

[Ryan Friedman (ryanf55)]

For portability, this at least does that change only on Linux:

if(CMAKE_SYSTEM_NAME STREQUAL Linux)
  list(APPEND CMAKE_MODULE_PATH /usr/share/cmake/geographiclib)
endif()

This is a potential patch that fixes Ubuntu 22.04.

[Ryan Friedman (ryanf55)]

Hello,

If I found a backwards-compatible fix, is there any possibility it could be backported to Ubuntu Jammy? If so, I am happy to contribute one.

[Naël (nathanael-naeri)]

Can confirm that Ryan's CMake code in comment #4 works around this issue in Ubuntu 20.04.