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.

1 files changed, 5 insertions, 4 deletions

diff --git a/src/buildtool/compatibility/native_support.hpp b/src/buildtool/compatibility/native_support.hpp
index cb7b147f..449117c9 100644
--- a/src/buildtool/compatibility/native_support.hpp
+++ b/src/buildtool/compatibility/native_support.hpp
@@ -17,9 +17,10 @@
 
 #include <string>
 
-#include <gsl-lite/gsl-lite.hpp>
-
 #include "src/buildtool/compatibility/compatibility.hpp"
+#include "src/utils/cpp/gsl.hpp"
+
+#include <gsl/gsl>
 
 /// \brief Helper functions to support the native remote-execution protocol.
 class NativeSupport {
@@ -44,7 +45,7 @@ class NativeSupport {
         if (Compatibility::IsCompatible()) {
             return hash;
         }
-        gsl_ExpectsAudit(not IsPrefixed(hash));
+        ExpectsAudit(not IsPrefixed(hash));
         return (is_tree ? kTreeTag : kBlobTag) + hash;
     }
 
@@ -53,7 +54,7 @@ class NativeSupport {
         if (Compatibility::IsCompatible()) {
             return hash;
         }
-        gsl_ExpectsAudit(IsPrefixed(hash));
+        ExpectsAudit(IsPrefixed(hash));
         return hash.substr(kTagLength);
     }