util.hh: Move nativeSystem to local-derivation-goal.cc

Change-Id: I74565fbfd3aeedef8f50465808fac712b84e47ad

src/libstore/build/local-derivation-goal.cc

@@ -64,6 +64,11 @@ extern "C" int sandbox_init_with_parameters(const char *profile, uint64_t flags,
 
 namespace nix {
 
+/**
+ * The system for which Nix is compiled.
+ */
+constexpr std::string_view nativeSystem = SYSTEM;
+
 void handleDiffHook(
     uid_t uid, uid_t gid,
     const Path & tryA, const Path & tryB,

src/libutil/error.cc

@@ -10,8 +10,6 @@
 
 namespace nix {
 
-const std::string nativeSystem = SYSTEM;
-
 void BaseError::addTrace(std::shared_ptr<Pos> && e, HintFmt hint)
 {
     err.traces.push_front(Trace { .pos = std::move(e), .hint = hint });

src/libutil/util.hh

@@ -33,11 +33,6 @@ namespace nix {
 struct Sink;
 struct Source;
 
-/**
- * The system for which Nix is compiled.
- */
-extern const std::string nativeSystem;
-