CMakeLists.txt does properly native MacOS with Xcode

[tlanc007]

The logic in the CMakeLists.txt doesn't recognize the native MacOS (Xcode) compiler as a clang compiler. The result is that the examples won't build as the search paths and compiler options are wrong.

The work around is to specify a true clang/llvm compiler when running cmake.

[jefftrull]

Would it be correct to rename this issue as follows: "Fails to build under MacOS with XCode"?

[tlanc007]

Sure. I just renamed it.

[jefftrull]

I had no trouble building on MacOS/Xcode using the develop branch. Here are the steps I used:

tar xjf ~/Downloads/boost_1_70_0.tar.bz
cd boost_1_70
./bootstrap.sh
./b2 --with-test --with-system --with-filesystem
cd ..
git clone https://github.com/cierelabs/boostache.git
cd boostache
git checkout develop
mkdir build
cd build
cmake -G Xcode -DBOOST_ROOT=~/work/ciere/boost_1_70_0 ..
xcodebuild -scheme ALL_BUILD
# test
examples/Debug/example1 # etc.

[tlanc007]

Sorry, I wasn't clear. I wasn't referring to the Xcode as a generator. There is an issue when using the native compiler for Makefile generation. That is why I didn't use Xcode as the original subject.

cmake -DBoost_NO_BOOST_CMAKE=true -G "Unix Makefiles" ..

The -std option is never passed to the compiler and so there will be errors like:

boostache/include/boost/boostache/vm/traits.hpp:76:32: error:
a space is required between consecutive right angle brackets (use '> >')
struct is_map<std::map<T1,T2>>

But:
CC=clang CXX=clang++ cmake -DBoost_NO_BOOST_CMAKE=true -G "Unix Makefiles" ..

is fine, assuming one's path is pointing to different compilers than the native ones provided by Xcode.

[jefftrull]

I'm not seeing this issue...

For Unix Makefiles it finds (without my help) /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/c++

I used cmake -G "Unix Makefiles" -DBOOST_ROOT=/blah/blah .. without any special environment changes. Adding -DBoost_NO_BOOST_CMAKE=true makes no difference.

I wonder if it's an Xcode setup issue. I did have to do sudo xcode-select --reset for the Xcode generator previously. Maybe try it?