CMake fails to run with BOOST_ROOT set (no system boost)

[CJCombrink]

Issue Description

CMake fails to run when using BOOST_ROOT instead of system root

• "host/cmake/Modules/UHDAtomics.cmake" does not find boost if boost is specified using "BOOST_ROOT" cmake definition (not in system installs)

Setup Details

Clean Debian 11 environment, like docker.

1. Install GCC11 (build from source probably)
2. Download and build boost from source
3. For UHD run cmake with BOOST_ROOT set to path where boost was downloaded to, with c++std=20
4. Cmake fails to detect atomics

Expected Behavior

UHD Compiles and works

Actual Behaviour

CMake fails to configure uhd and build.

Steps to reproduce the problem

docker run -it --rm gcc:11
apt update
apt install -y cmake python3-mako
# get boost
cd /
wget https://boostorg.jfrog.io/artifactory/main/release/1.79.0/source/boost_1_79_0.tar.gz
tar -xf boost_1_79_0.tar.gz
cd boost_1_79_0
./bootstrap.sh --prefix=/boost/1.79/
./b2
./b2 install
# get uhd
cd /
git clone https://github.com/EttusResearch/uhd.git
cd uhd 
git checkout v4.2.0.0
# run cmake
mkdir -p host/build && cd host/build
cmake -DBOOST_ROOT=/boost/1.79/ ..

Error from CMAKE:

...
--   Boost version: 1.79.0
--   Boost include directories: /boost/1.79/include
--   Boost library directories: /boost/1.79/lib
--   Boost libraries: /boost/1.79/lib/libboost_chrono.so;/boost/1.79/lib/libboost_date_time.so;/boost/1.79/lib/libboost_filesystem.so;/boost/1.79/lib/libboost_program_options.so;/boost/1.79/lib/libboost_serialization.so;/boost/1.79/lib/libboost_thread.so;-lpthread;/boost/1.79/lib/libboost_unit_test_framework.so;/boost/1.79/lib/libboost_system.so;/boost/1.79/lib/libboost_atomic.so
-- Looking for Boost version 1.65 or greater - found
...
-- Configuring atomics support...
-- Performing Test HAVE_CXX_ATOMICS_WITHOUT_LIB
-- Performing Test HAVE_CXX_ATOMICS_WITHOUT_LIB - Success
-- Performing Test HAVE_CXX_ATOMICS64_WITHOUT_LIB
-- Performing Test HAVE_CXX_ATOMICS64_WITHOUT_LIB - Success
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITHOUT_LIB
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITHOUT_LIB - Failed
-- Looking for __atomic_fetch_add_4 in atomic
-- Looking for __atomic_fetch_add_4 in atomic - found
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITH_LIB
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITH_LIB - Failed
CMake Error at cmake/Modules/UHDAtomics.cmake:102 (message):
  Host compiler must support std::atomic!
Call Stack (most recent call first):
  lib/utils/CMakeLists.txt:187 (CHECK_ATOMICS_LIB_REQUIRED)
  lib/CMakeLists.txt:46 (include)
  lib/CMakeLists.txt:93 (INCLUDE_SUBDIRECTORY)

Additional Information

If I apply the following patch cmake works:

diff --git a/host/cmake/Modules/UHDAtomics.cmake b/host/cmake/Modules/UHDAtomics.cmake
index eb2800f..560bfce 100644
--- a/host/cmake/Modules/UHDAtomics.cmake
+++ b/host/cmake/Modules/UHDAtomics.cmake
@@ -10,0 +11,2 @@
+set(CMAKE_REQUIRED_INCLUDES ${BOOST_ROOT}/include) 
+

clean build folder and rerun cmake:

-- Configuring atomics support...
-- Performing Test HAVE_CXX_ATOMICS_WITHOUT_LIB
-- Performing Test HAVE_CXX_ATOMICS_WITHOUT_LIB - Success
-- Performing Test HAVE_CXX_ATOMICS64_WITHOUT_LIB
-- Performing Test HAVE_CXX_ATOMICS64_WITHOUT_LIB - Success
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITHOUT_LIB
-- Performing Test HAVE_CXX_BOOST_ATOMICS_WITHOUT_LIB - Success
--   Atomics support is built-in, no linking required.

[CJCombrink]

I have tested with the master branch (commit 5333d3d (HEAD -> master, origin/master, origin/HEAD) and the issue is still there.

The patch above for property_tree.ipp does not work on the master branch but the issue is still present

[CJCombrink]

I updated the issue after creation to remove an unrelated issue, will file a separate issue for that one.
Created: #589

[b00ga]

I ran into this issue today as well.

• UHD 4.2.0.0 release
• AlmaLinux 8
• Boost 1.69 from Alma boost169 family of packages (dnf install boost169-devel) (installs includes to /usr/include/boost169/ and libs to /usr/lib64/boost169/)
• Hinting cmake with -DBoost_INCLUDE_DIR=/usr/include/boost169 -DBoost_LIBRARY_DIR=/usr/lib64/boost169/ command line options (for use by host/cmake/Modules/UHDBoost.cmake).

I made a similar-ish fix. Based on these docs: https://cmake.org/cmake/help/latest/module/CheckCXXSourceCompiles.html
I set CMAKE_REQUIRED_INCLUDES.

Here's my diff (from master to my modified cmake file in 4.2.0.0 release).

$ diff -urN uhd/host/cmake/Modules/UHDAtomics.cmake uhd-4.2.0.0/host/cmake/Modules/UHDAtomics.cmake 
--- uhd/host/cmake/Modules/UHDAtomics.cmake	2022-05-16 18:01:59.170208258 +0000
+++ uhd-4.2.0.0/host/cmake/Modules/UHDAtomics.cmake	2022-05-16 18:04:03.809489339 +0000
@@ -36,6 +36,7 @@
 # Note: If we reach this, we have already checked for the existence of Boost,
 # and Boost.Lockfree is a header-only library so no linker options required.
 function(CHECK_WORKING_CXX_BOOST_ATOMICS varname)
+    list(APPEND CMAKE_REQUIRED_INCLUDES ${Boost_INCLUDE_DIRS})
     CHECK_CXX_SOURCE_COMPILES("
         #include <boost/lockfree/queue.hpp>
         boost::lockfree::queue<int> queue(1);