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  TODO: .ci/Makefile is obsolete now, as well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, 46 insertions, 0 deletions

diff --git a/.github/actions/check-symbols/action.yml b/.github/actions/check-symbols/action.yml
new file mode 100644
index 0000000..7428be3
--- /dev/null
+++ b/.github/actions/check-symbols/action.yml
@@ -0,0 +1,46 @@
+name: Check symbols
+description: Check debug symbols
+inputs:
+  path:
+    description: Installation directory
+    required: true
+  expected:
+    description: Expected symbols
+    required: true
+runs:
+  using: composite
+  steps:
+    - run: |
+        $install_dir = '${{ inputs.path }}'
+        $bin_dir = Join-Path $install_dir 'bin'
+        $lib_dir = Join-Path $install_dir 'lib'
+
+        $script_path = if ($env:CI_TARGET_ELF) {
+            Join-Path $env:GITHUB_WORKSPACE '.ci' 'verify_symbols.sh'
+        } else {
+            throw "Verifying symbols for PE executables is not implemented"
+        }
+
+        ConvertFrom-Json '${{ inputs.expected }}' | %{
+            $target = $_.target
+            $type = $_.type
+
+            switch -Exact ($type) {
+                'exe' {
+                    $file = $target + $env:CI_EXE_EXT
+                    $path = Join-Path $bin_dir $file
+                }
+                'dll' {
+                    $file = $env:CI_DLL_PREFIX + $target + $env:CI_DLL_EXT
+                    $path = if ($env:CI_DLL_IN_BIN) {
+                        Join-Path $bin_dir $file
+                    } else {
+                        Join-Path $lib_dir $file
+                    }
+                }
+                default { throw "Unrecognized type: $type" }
+            }
+
+            & $script_path $path $_.symbols
+        }
+      shell: pwsh