Problems with gcc > v4.9

[TillmanOttBA]

Hi,

I have a Problem installing orocos from source. Not that I necessarily want to create it from source, but apt-get install ros-melodic-orocos-toolchain doesn't seem to exist.

On my system gcc is installed in the current version (7.4.0). It seems that version 3.x or 4.x is needed to built orocos_toolchain.

Is there a way to install orocos_toolchain anyway?

Thank you,
Tillman

<== Finished processing package [3 of 9]: 'orogen'

==> Processing plain cmake package: 'rtt'
==> Creating build directory: 'build_isolated/rtt/devel'
==> Building with env: '/home/tillmanott/orocos_ws/devel_isolated/orogen/env.sh'
==> cmake /home/tillmanott/orocos_ws/src/rtt -DCMAKE_INSTALL_PREFIX=/home/tillmanott/orocos_ws/devel_isolated/rtt -G Unix Makefiles in '/home/tillmanott/orocos_ws/build_isolated/rtt/devel'
-- The C compiler identification is GNU 7.4.0
-- The CXX compiler identification is GNU 7.4.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
Orocos RTT version  (2.7.0)
No orocos-rtt.cmake file loaded, using default settings.See orocos-rtt.default.cmake
No OROCOS_TARGET environment variable set. Using: gnulinux
-- CMAKE_VERSION: 3.10.2
-- Boost version: 1.65.1
-- Using the following Boost include directory: /usr/include
-- Found the following Boost libraries:
--   filesystem: /usr/lib/x86_64-linux-gnu/libboost_filesystem.so
--   system: /usr/lib/x86_64-linux-gnu/libboost_system.so
--   unit_test_framework: /usr/lib/x86_64-linux-gnu/libboost_unit_test_framework.so
--   thread: /usr/lib/x86_64-linux-gnu/libboost_thread.so
--   serialization: /usr/lib/x86_64-linux-gnu/libboost_serialization.so
Boost found in /usr/include
-- Found Xerces: /usr/lib/x86_64-linux-gnu/libxerces-c.so  
Orocos target is gnulinux
-- Found PTHREAD 
**ERROR: You seem to be using gcc version:
7

CMake Error at config/check_depend.cmake:315 (MESSAGE):
  ERROR: For gcc, Orocos requires version 4.x or 3.x
Call Stack (most recent call first):
  CMakeLists.txt:112 (INCLUDE)**


-- Configuring incomplete, errors occurred!
See also "/home/tillmanott/orocos_ws/build_isolated/rtt/devel/CMakeFiles/CMakeOutput.log".
<== Failed to process package 'rtt': 
  Command '['/home/tillmanott/orocos_ws/devel_isolated/orogen/env.sh', 'cmake', '/home/tillmanott/orocos_ws/src/rtt', '-DCMAKE_INSTALL_PREFIX=/home/tillmanott/orocos_ws/devel_isolated/rtt', '-G', 'Unix Makefiles']' returned non-zero exit status 1

Reproduce this error by running:
==> cd /home/tillmanott/orocos_ws/build_isolated/rtt && /home/tillmanott/orocos_ws/devel_isolated/orogen/env.sh cmake /home/tillmanott/orocos_ws/src/rtt -DCMAKE_INSTALL_PREFIX=/home/tillmanott/orocos_ws/devel_isolated/rtt -G 'Unix Makefiles'

Command failed, exiting.

[meyerj]

The compatibility with GCC 5 and newer has been fixed in orocos-toolchain/rtt#200 in 2017, by removing the version check completely.

Apparently you tried to build version 2.7.0, which indeed does not have this patch yet. Maybe the default branch or the submodules were not up-to-date back then...