GIANT CLUSTERFUCK OF A COMMIT

OK, this is epic.  I was basically just trying to a) support Clang and
b) add more test coverage.  _THREE MONTHS_ and a few hundred CI runs
later, this is what I came up with.  I don't know how it ended up being
what it is, but here we go.

Some highlights of the changes:

1) CI builds has been moved to GitHub Actions,
2) the entire notion of a toolchain has been reworked; it now supports
Clang on all platforms.

* .github: this directory contains the GitHub Actions workflow
scripts/actions.  In the process, I created like 6 external GitHub
actions, but it's still pretty massive.  An upside is that it covers
much more platform/toolchain combinations _and_ check a lot of the
expected post-conditions.  TODO: .ci/Makefile is obsolete now, as well
as .travis.yml and .appveyor.yml.

* common.cmake: added Clang support.  In the process, a great deal has
been learned about how CMake works; in particular, static runtime
support has been reworked to be more robust.

* project: the entire notion of a "toolchain" has been reworked.
Instead of a measly --mingw parameter, there's now a separate --toolset
parameter, which allows you to choose between GCC, Clang, MSVC, etc.
Both Boost and CMake build scripts were enhanced greatly to support
Clang and other toolchains in a more robust way.

1 files changed, 63 insertions, 0 deletions

diff --git a/.github/actions/software-environment/action.yml b/.github/actions/software-environment/action.yml
new file mode 100644
index 0000000..c8a416b
--- /dev/null
+++ b/.github/actions/software-environment/action.yml
@@ -0,0 +1,63 @@
+name: Set up software environment
+description: Set up software paths and versions
+inputs:
+  toolset:
+    description: Toolset to use
+    required: true
+  platform:
+    description: Target platform
+    required: false
+    default: x64
+runs:
+  using: composite
+  steps:
+    - run: |
+        if ($env:CI_HOST_WINDOWS) {
+            echo 'C:\Program Files\CMake\bin' >> $env:GITHUB_PATH
+        }
+      shell: pwsh
+    - run: |
+        echo '------------------------------------------------------------'
+        echo 'PATH'
+        echo '------------------------------------------------------------'
+        echo $env:PATH.Split([IO.Path]::PathSeparator)
+      shell: pwsh
+    - run: |
+        function Print-Info {
+            param(
+                [Parameter(Mandatory=$true)]
+                [string] $name,
+                [Parameter(Mandatory=$true)]
+                [string] $exe
+            )
+
+            echo ''
+            echo '------------------------------------------------------------'
+            echo $name
+            echo '------------------------------------------------------------'
+            $full_path = Get-Command $exe -ErrorAction SilentlyContinue
+            if ($full_path) {
+                $full_path = $full_path.Path
+                echo "Location: $full_path"
+                echo 'Version info:'
+                & $full_path --version
+            } else {
+                echo "Executable '$name' couldn't be found!"
+            }
+        }
+
+        $python = 'python'
+        if ($env:CI_HOST_CYGWIN) {
+            $python = 'python3'
+        }
+
+        Print-Info 'python' $python
+        Print-Info 'cmake' 'cmake'
+        Print-Info 'make' 'make'
+        Print-Info 'mingw32-make' 'mingw32-make'
+        Print-Info 'g++' 'g++'
+        Print-Info 'clang++' 'clang++'
+        Print-Info 'clang-cl' 'clang-cl'
+        Print-Info 'i686-w64-mingw32-g++' 'i686-w64-mingw32-g++'
+        Print-Info 'x86_64-w64-mingw32-g++' 'x86_64-w64-mingw32-g++'
+      shell: pwsh