imports: Switch to Microsoft GSL implementation

... with two minor code base changes compared to previous
use of gsl-lite:

- dag.hpp: ActionNode::Ptr and ArtifactNode::Ptr are not
  wrapped in gsl::not_null<> anymore, due to lack of support
  for wrapping std::unique_ptr<>. More specifically, the
  move constructor is missing, rendering it impossible to
  use std::vector<>::emplace_back().

- utils/cpp/gsl.hpp: New header file added to implement the
  macros ExpectsAudit() and EnsureAudit(), asserts running
  only in debug builds, which were available in gsl-lite but
  are missing in MS GSL.

5 files changed, 25 insertions, 37 deletions

diff --git a/etc/defaults/CC/TARGETS.just b/etc/defaults/CC/TARGETS.just
index ea501e09..66033bef 100644
--- a/etc/defaults/CC/TARGETS.just
+++ b/etc/defaults/CC/TARGETS.just
@@ -12,21 +12,13 @@
     , "-pedantic-errors"
     ]
   , "ADD_CXXFLAGS":
-    { "type": "++"
-    , "$1":
-      [ [ "-std=c++20"
-        , "-Wall"
-        , "-Wextra"
-        , "-Wpedantic"
-        , "-Wsign-conversion"
-        , "-Werror"
-        , "-pedantic-errors"
-        ]
-      , { "type": "if"
-        , "cond": {"type": "var", "name": "DEBUG"}
-        , "then": ["-Dgsl_CONFIG_CONTRACT_CHECKING_AUDIT=1"]
-        }
-      ]
-    }
+    [ "-std=c++20"
+    , "-Wall"
+    , "-Wextra"
+    , "-Wpedantic"
+    , "-Wsign-conversion"
+    , "-Werror"
+    , "-pedantic-errors"
+    ]
   }
 }
diff --git a/etc/dev/TARGETS b/etc/dev/TARGETS
index 40fdcf52..725f884e 100644
--- a/etc/dev/TARGETS
+++ b/etc/dev/TARGETS
@@ -11,7 +11,7 @@
   , "targets":
     [ ["@", "ssl", "", "crypto"]
     , ["@", "grpc", "", "grpc++"]
-    , ["@", "gsl-lite", "", "gsl-lite"]
+    , ["@", "gsl", "", "gsl"]
     , ["@", "fmt", "", "fmt"]
     , ["@", "cli11", "", "cli11"]
     , ["@", "json", "", "json"]
diff --git a/etc/import.pkgconfig/TARGETS.gsl b/etc/import.pkgconfig/TARGETS.gsl
index e73040f5..866c3fcf 100644
--- a/etc/import.pkgconfig/TARGETS.gsl
+++ b/etc/import.pkgconfig/TARGETS.gsl
@@ -1,5 +1,3 @@
-{ "gsl-lite":
-  { "type": ["@", "rules", "CC/pkgconfig", "system_library"]
-  , "name": ["gsl-lite"]
-  }
+{ "gsl":
+  {"type": ["@", "rules", "CC/pkgconfig", "system_library"], "name": ["gsl"]}
 }
diff --git a/etc/import/TARGETS.gsl b/etc/import/TARGETS.gsl
index d22e25b2..a769eac9 100644
--- a/etc/import/TARGETS.gsl
+++ b/etc/import/TARGETS.gsl
@@ -1,11 +1,7 @@
-{ "gsl-lite":
+{ "gsl":
   { "type": ["@", "rules", "CC", "library"]
-  , "name": ["gsl-lite"]
-  , "hdrs": ["gsl-lite hdrs"]
-  }
-, "gsl-lite hdrs":
-  { "type": "tree"
-  , "name": "gsl-lite"
-  , "deps": ["gsl", "gsl-lite.h", "gsl-lite.hpp", "gsl-lite-vc6.hpp"]
+  , "name": ["gsl"]
+  , "hdrs": [["TREE", null, "."]]
+  , "stage": ["gsl"]
   }
 }
diff --git a/etc/repos.json b/etc/repos.json
index f6bfb68b..44bf6698 100644
--- a/etc/repos.json
+++ b/etc/repos.json
@@ -5,7 +5,7 @@
     , "bindings":
       { "rules": "rules-just"
       , "just-distfiles": "just-distfiles"
-      , "gsl-lite": "gsl-lite"
+      , "gsl": "com_github_microsoft_gsl"
       , "cli11": "cli11"
       , "json": "json"
       , "fmt": "fmt"
@@ -27,7 +27,7 @@
     { "repository":
       { "type": "distdir"
       , "repositories":
-        [ "gsl-lite"
+        [ "com_github_microsoft_gsl"
         , "cli11"
         , "json"
         , "fmt"
@@ -138,18 +138,20 @@
       {"type": "file", "path": "etc/import", "pragma": {"to_git": true}}
     , "pkg_bootstrap": {"local_path": "etc/import.pkgconfig"}
     }
-  , "gsl-lite":
+  , "com_github_microsoft_gsl":
     { "repository":
       { "type": "archive"
-      , "content": "6a2245941d8a713897f439c35512593683f6ad48"
-      , "fetch": "https://github.com/gsl-lite/gsl-lite/archive/v0.40.0.tar.gz"
-      , "sha256": "65af4ec8a1050dac4f1ca4622881bb02a9c3978a9baec289fb56e25412d6cac7"
-      , "sha512": "afd65009bf33f54cd1caf1988b725e618bee4f4f779825ae1df55017034c6fff75feaa737a358a7f5e690757637f4d281c2f22d06c39efb81dacd7d1949251df"
-      , "subdir": "gsl-lite-0.40.0/include/gsl"
+      , "content": "386f0a89a47763481223a63d5026215af8d3c827"
+      , "fetch": "https://github.com/microsoft/GSL/archive/refs/tags/v4.0.0.tar.gz"
+      , "sha256": "f0e32cb10654fea91ad56bde89170d78cfbf4363ee0b01d8f097de2ba49f6ce9"
+      , "sha512": "7fa7446796c6bf82fb3bff09f86a69c446a27be528bef3b17c8bc5ad2f24d5cf86bdb3d3813ecb44726e8f395020180e97e41027330d1fbf545cc0f0b44aac29"
+      , "subdir": "GSL-4.0.0/include/gsl"
       }
     , "target_root": "import targets"
     , "target_file_name": "TARGETS.gsl"
     , "bindings": {"rules": "rules"}
+    , "bootstrap": {"include_name": "gsl"}
+    , "pkg_bootstrap": {"local_path": "include/gsl"}
     }
   , "cli11":
     { "repository":