add_custom_command: Target-dependent generator expression support

OUTPUT variant with a TARGET given to allow resolving target-based generator
expressions wouldn't work because OUTPUT is resolved before generator targets
are created, i.e. FindGeneratorTargetToUse() returns nullptr.
This is a known limitation, see #21364.

Implements #21336.

1 files changed, 5 insertions, 0 deletions

diff --git a/Source/cmCustomCommand.h b/Source/cmCustomCommand.h
index e22c7a4..5cbd3d1 100644
--- a/Source/cmCustomCommand.h
+++ b/Source/cmCustomCommand.h
@@ -100,6 +100,10 @@ public:
   cmPolicies::PolicyStatus GetCMP0116Status() const;
   void SetCMP0116Status(cmPolicies::PolicyStatus cmp0116);
 
+  /** Set/Get the associated target */
+  const std::string& GetTarget() const;
+  void SetTarget(const std::string& target);
+
 private:
   std::vector<std::string> Outputs;
   std::vector<std::string> Byproducts;
@@ -107,6 +111,7 @@ private:
   cmCustomCommandLines CommandLines;
   cmListFileBacktrace Backtrace;
   cmImplicitDependsList ImplicitDepends;
+  std::string Target;
   std::string Comment;
   std::string WorkingDirectory;
   std::string Depfile;