Use conda compiler toolchain for conda builds

For both libastra and astra-toolbox:

1) We do not use script_env to set CC/CXX anymore, since the compilers
   are installed by conda.
2) The build string is made useful by including either the python+numpy
   version or the cudatoolkit version that the package was built with.
3) Some clean-up of build.sh in buildenv/

For libastra:

1) The libastra.so is built with the conda C/C++ compiler
   toolchain. This has two benefits:
   1) The rpath of libastra.so is set to $ORIGIN, which makes linking
      easier for dependent packages.
   2) libastra.so is linkable against ancient versions of glibc. With
      old versions of memcpy.
2) The C/C++ compiler version is fixed to 5.4.0
3) In libastra/build.sh, we rename $CONDA_PREFIX to
   $PREFIX. Apparently, this is how it is supposed to be done. For me,
   $CONDA_PREFIX was suddenly undefined. Why this was not a problem
   before, is unclear to me.
4) The cudatoolkit runtime dependency is pinned with pin_compatible
5) The libastra conda package now provides headers and .pc file. This
   is useful for building C++ packages that depend on astra.
6) Remove some old code related to cudatoolkit<8.0.

For astra-toolbox:

1) astra-toolbox uses the conda-provided compilers
2) The compilers are fixed to version 7.3
3) Add boost to host requirements of astra-toolbox

Notes on testing:

- The libastra build has been tested with all versions of cudatoolkit
- The astra-toolbox build has been tested with all provided versions
  of python after building a single cudatoolkit version of libastra.

How to test this branch:

- It should work by just editing
  `python/conda/linux_release/buildenv/build.sh`. Set
  BRANCH=CI-use-conda-c-compiler-toolchain
  URL=https://github.com/ahendriksen/astra-toolbox

  and run release.sh from the `python/conda/linux_release` directory.

9 files changed, 52 insertions, 29 deletions

diff --git a/python/conda/astra-toolbox/conda_build_config_py27.yaml b/python/conda/astra-toolbox/conda_build_config_py27.yaml
index f119b61..869d22e 100644
--- a/python/conda/astra-toolbox/conda_build_config_py27.yaml
+++ b/python/conda/astra-toolbox/conda_build_config_py27.yaml
@@ -8,3 +8,8 @@ numpy:
   - 1.14
   - 1.15
   - 1.16
+
+c_compiler_version:
+  - 7.3
+cxx_compiler_version:
+  - 7.3
diff --git a/python/conda/astra-toolbox/conda_build_config_py35.yaml b/python/conda/astra-toolbox/conda_build_config_py35.yaml
index 8dd963c..72d4cef 100644
--- a/python/conda/astra-toolbox/conda_build_config_py35.yaml
+++ b/python/conda/astra-toolbox/conda_build_config_py35.yaml
@@ -3,3 +3,7 @@ python:
 
 numpy:
   - 1.15
+c_compiler_version:
+  - 7.3
+cxx_compiler_version:
+  - 7.3
diff --git a/python/conda/astra-toolbox/conda_build_config_py36.yaml b/python/conda/astra-toolbox/conda_build_config_py36.yaml
index f043435..996e22c 100644
--- a/python/conda/astra-toolbox/conda_build_config_py36.yaml
+++ b/python/conda/astra-toolbox/conda_build_config_py36.yaml
@@ -5,3 +5,7 @@ numpy:
   - 1.14
   - 1.15
   - 1.16
+c_compiler_version:
+  - 7.3
+cxx_compiler_version:
+  - 7.3
diff --git a/python/conda/astra-toolbox/conda_build_config_py37.yaml b/python/conda/astra-toolbox/conda_build_config_py37.yaml
index ebbf44a..4282407 100644
--- a/python/conda/astra-toolbox/conda_build_config_py37.yaml
+++ b/python/conda/astra-toolbox/conda_build_config_py37.yaml
@@ -6,3 +6,7 @@ numpy:
   - 1.14
   - 1.15
   - 1.16
+c_compiler_version:
+  - 7.3
+cxx_compiler_version:
+  - 7.3
diff --git a/python/conda/astra-toolbox/meta.yaml b/python/conda/astra-toolbox/meta.yaml
index 054751b..b3c036b 100644
--- a/python/conda/astra-toolbox/meta.yaml
+++ b/python/conda/astra-toolbox/meta.yaml
@@ -8,8 +8,7 @@ source:
 
 build:
   number: 0
-  script_env:
-    - CC # [linux]
+  string: py_{{ python }}_numpy_{{ numpy }}
 
 test:
   imports:
@@ -24,14 +23,17 @@ test:
 
 requirements:
   build:
+    - {{ compiler('c') }}    # [win or linux]
+    - {{ compiler('cxx') }}  # [linux]
+  host:
     - python
     - cython >=0.13
+    - boost # [osx or linux]
     - nomkl # [not win]
     - numpy {{ numpy }}
     - scipy
     - six
     - libastra ==1.9.0.dev11
-
   run:
     - python
     - {{ pin_compatible('numpy', min_pin='x.x', max_pin='x.x') }}
diff --git a/python/conda/libastra/build.sh b/python/conda/libastra/build.sh
index d19c7af..4e48ba6 100644..100755
--- a/python/conda/libastra/build.sh
+++ b/python/conda/libastra/build.sh
@@ -18,35 +18,27 @@ cd $SRC_DIR/build/linux
 
 $SRC_DIR/build/linux/autogen.sh
 
-# Add C++11 to compiler flags if nvcc supports it, mostly to work around a boost bug
+# Add C++11 to compiler flags, mostly to work around a boost bug.
+# Since we require cudatoolkit>=8.0 nvcc supports this.
 NVCC=$CUDA_ROOT/bin/nvcc
-echo "int main(){return 0;}" > $CONDA_PREFIX/test.cu
-$NVCC $CONDA_PREFIX/test.cu -ccbin $CC --std=c++11 -o $CONDA_PREFIX/test.out > /dev/null 2>&1 && EXTRA_NVCCFLAGS="--std=c++11" || true
-rm -f $CONDA_PREFIX/test.out $CONDA_PREFIX/test.cu
+EXTRA_NVCCFLAGS="--std=c++11"
 
-$SRC_DIR/build/linux/configure --with-install-type=prefix --with-cuda=$CUDA_ROOT --prefix=$CONDA_PREFIX NVCCFLAGS="-ccbin $CC -I$CONDA_PREFIX/include $EXTRA_NVCCFLAGS" CC=$CC CXX=$CXX CPPFLAGS="-I$CONDA_PREFIX/include"
+
+$SRC_DIR/build/linux/configure --with-install-type=prefix --with-cuda=$CUDA_ROOT --prefix=$PREFIX NVCCFLAGS="-ccbin $CC -I$PREFIX/include $EXTRA_NVCCFLAGS" CC=$CC CXX=$CXX CPPFLAGS="-I$PREFIX/include"
 
 # Clean, because we may be re-using this source tree when building
 # multiple variants of this conda package.
 make clean
 
-make -j $CPU_COUNT install-libraries
+make -j $CPU_COUNT
+make -j $CPU_COUNT install-dev
 
 
 test -d $CUDA_ROOT/lib64 && LIBPATH="$CUDA_ROOT/lib64" || LIBPATH="$CUDA_ROOT/lib"
 
 case `uname` in
   Darwin*)
-    cp -P $LIBPATH/libcudart.*.dylib $CONDA_PREFIX/lib
-    cp -P $LIBPATH/libcufft.*.dylib $CONDA_PREFIX/lib
-    ;;
-  Linux*)
-    if [ "$cudatoolkit" = "7.0" ]; then
-      # For some reason conda-build adds these symlinks automatically for
-      # cudatoolkit-5.5 and 6.0, but not 7.0. For 7.5 these symlinks are not
-      # necessary, and for 8.0 the cudatoolkit packages includes them.
-      ln -T -s libcudart.so.7.0.28 $CONDA_PREFIX/lib/libcudart.so.7.0
-      ln -T -s libcufft.so.7.0.35 $CONDA_PREFIX/lib/libcufft.so.7.0
-    fi
+    cp -P $LIBPATH/libcudart.*.dylib $PREFIX/lib
+    cp -P $LIBPATH/libcufft.*.dylib $PREFIX/lib
     ;;
 esac
diff --git a/python/conda/libastra/linux_build_config.yaml b/python/conda/libastra/linux_build_config.yaml
index 41db828..b415b4a 100644
--- a/python/conda/libastra/linux_build_config.yaml
+++ b/python/conda/libastra/linux_build_config.yaml
@@ -4,3 +4,7 @@ cudatoolkit:
   - 9.2
   - 10.0
   - 10.1
+c_compiler_version:    # [linux or win]
+  - 5.4                # [linux or win]
+cxx_compiler_version:  # [linux or win]
+  - 5.4                # [linux or win]
diff --git a/python/conda/libastra/meta.yaml b/python/conda/libastra/meta.yaml
index 59c3a09..407929b 100644
--- a/python/conda/libastra/meta.yaml
+++ b/python/conda/libastra/meta.yaml
@@ -8,21 +8,22 @@ source:
 
 build:
   number: 0
-  script_env:
-    - CC # [linux]
-    - CXX # [linux]
+  string: cuda_{{ cudatoolkit }} # [linux]
 
 requirements:
   build:
-    - {{compiler('c')}} # [win]
+    - {{ compiler('c') }}    # [win or linux]
+    - {{ compiler('cxx') }}  # [linux]
     - boost # [osx]
     - automake # [osx]
     - autoconf # [osx]
     - libtool # [osx]
+  host:
+    - boost # [osx or linux]
     - cudatoolkit {{ cudatoolkit }} # [linux]
-
   run:
-    - cudatoolkit {{ cudatoolkit }} # [linux]
+    # See: https://github.com/conda-forge/conda-forge.github.io/issues/687#issuecomment-460095230
+    - {{ pin_compatible('cudatoolkit', max_pin='x.x') }} # [linux]
 
 about:
   home: http://www.astra-toolbox.com
diff --git a/python/conda/linux_release/buildenv/build.sh b/python/conda/linux_release/buildenv/build.sh
index cc6dc31..158c1d5 100644..100755
--- a/python/conda/linux_release/buildenv/build.sh
+++ b/python/conda/linux_release/buildenv/build.sh
@@ -1,16 +1,23 @@
 #!/bin/sh
 
-export CC=gcc
-export CXX=g++
+set -e
+
+BRANCH=master
+URL=https://github.com/astra-toolbox/astra-toolbox
+
+echo "Cloning from ${URL}"
+echo "        branch: ${BRANCH}"
 
 cd /root
-git clone --depth 1 --branch master https://github.com/astra-toolbox/astra-toolbox
+git clone --depth 1 --branch ${BRANCH} ${URL}
+
 [ $# -eq 0 ] || perl -pi -e "s/^(\s*version:\s*)[0-9a-z+\.']+$/\${1}'$1'/" astra-toolbox/python/conda/libastra/meta.yaml astra-toolbox/python/conda/astra-toolbox/meta.yaml
 [ $# -eq 0 ] || perl -pi -e "s/^(\s*number:\s*)[0-9]+$/\${1}$2/" astra-toolbox/python/conda/libastra/meta.yaml astra-toolbox/python/conda/astra-toolbox/meta.yaml
 [ $# -eq 0 ] || perl -pi -e "s/^(\s*-\s*libastra\s*==\s*)[0-9a-z+\.]+$/\${1}$1/" astra-toolbox/python/conda/astra-toolbox/meta.yaml
 
 
 conda-build -m astra-toolbox/python/conda/libastra/linux_build_config.yaml astra-toolbox/python/conda/libastra
+
 for i in 27 35 36 37; do
   conda-build -m astra-toolbox/python/conda/astra-toolbox/conda_build_config_py$i.yaml astra-toolbox/python/conda/astra-toolbox
 done