add_dependencies: Track backtraces internally

Record backtraces for "utility" dependencies created by
`add_dependencies` calls.

Source/cmGeneratorTarget.cxx

@@ -674,16 +674,13 @@ std::set<cmLinkItem> const& cmGeneratorTarget::GetUtilityItems() const
 {
   if (!this->UtilityItemsDone) {
     this->UtilityItemsDone = true;
-    std::set<std::string> const& utilities = this->GetUtilities();
-    for (std::string const& i : utilities) {
-      cmListFileBacktrace const* bt = this->GetUtilityBacktrace(i);
+    std::set<BT<std::string>> const& utilities = this->GetUtilities();
+    for (BT<std::string> const& i : utilities) {
       if (cmGeneratorTarget* gt =
-            this->LocalGenerator->FindGeneratorTargetToUse(i)) {
-        this->UtilityItems.insert(
-          cmLinkItem(gt, bt ? *bt : cmListFileBacktrace()));
+            this->LocalGenerator->FindGeneratorTargetToUse(i.Value)) {
+        this->UtilityItems.insert(cmLinkItem(gt, i.Backtrace));
       } else {
-        this->UtilityItems.insert(
-          cmLinkItem(i, bt ? *bt : cmListFileBacktrace()));
+        this->UtilityItems.insert(cmLinkItem(i.Value, i.Backtrace));
       }
     }
   }
@@ -1713,17 +1710,11 @@ cmListFileBacktrace cmGeneratorTarget::GetBacktrace() const
   return this->Target->GetBacktrace();
 }
 
-const std::set<std::string>& cmGeneratorTarget::GetUtilities() const
+const std::set<BT<std::string>>& cmGeneratorTarget::GetUtilities() const
 {
   return this->Target->GetUtilities();
 }
 
-const cmListFileBacktrace* cmGeneratorTarget::GetUtilityBacktrace(
-  const std::string& u) const
-{
-  return this->Target->GetUtilityBacktrace(u);
-}
-
 bool cmGeneratorTarget::HaveWellDefinedOutputFiles() const
 {
   return this->GetType() == cmStateEnums::STATIC_LIBRARY ||

Source/cmGeneratorTarget.h

@@ -273,8 +273,7 @@ public:
 
   cmListFileBacktrace GetBacktrace() const;
 
-  std::set<std::string> const& GetUtilities() const;
-  cmListFileBacktrace const* GetUtilityBacktrace(const std::string& u) const;
+  std::set<BT<std::string>> const& GetUtilities() const;
 
   bool LinkLanguagePropagatesToDependents() const
   {

Source/cmGlobalNinjaGenerator.cxx

@@ -19,6 +19,7 @@
 #include "cmGeneratedFileStream.h"
 #include "cmGeneratorExpressionEvaluationFile.h"
 #include "cmGeneratorTarget.h"
+#include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmLocalNinjaGenerator.h"
 #include "cmMakefile.h"
@@ -1008,10 +1009,11 @@ void cmGlobalNinjaGenerator::AppendTargetDepends(
 {
   if (target->GetType() == cmStateEnums::GLOBAL_TARGET) {
     // These depend only on other CMake-provided targets, e.g. "all".
-    std::set<std::string> const& utils = target->GetUtilities();
-    for (std::string const& util : utils) {
+    std::set<BT<std::string>> const& utils = target->GetUtilities();
+    for (BT<std::string> const& util : utils) {
       std::string d =
-        target->GetLocalGenerator()->GetCurrentBinaryDirectory() + "/" + util;
+        target->GetLocalGenerator()->GetCurrentBinaryDirectory() + "/" +
+        util.Value;
       outputs.push_back(this->ConvertToNinjaPath(d));
     }
   } else {

Source/cmGlobalVisualStudio71Generator.cxx

@@ -159,7 +159,7 @@ void cmGlobalVisualStudio71Generator::WriteProjectDepends(
 // executables to the libraries it uses are also done here
 void cmGlobalVisualStudio71Generator::WriteExternalProject(
   std::ostream& fout, const std::string& name, const char* location,
-  const char* typeGuid, const std::set<std::string>& depends)
+  const char* typeGuid, const std::set<BT<std::string>>& depends)
 {
   fout << "Project(\"{"
        << (typeGuid ? typeGuid : this->ExternalProjectType(location))
@@ -171,9 +171,10 @@ void cmGlobalVisualStudio71Generator::WriteExternalProject(
   // project instead of in the global section
   if (!depends.empty()) {
     fout << "\tProjectSection(ProjectDependencies) = postProject\n";
-    for (std::string const& it : depends) {
-      if (!it.empty()) {
-        fout << "\t\t{" << this->GetGUID(it) << "} = {" << this->GetGUID(it)
+    for (BT<std::string> const& it : depends) {
+      std::string const& dep = it.Value;
+      if (!dep.empty()) {
+        fout << "\t\t{" << this->GetGUID(dep) << "} = {" << this->GetGUID(dep)
              << "}\n";
       }
     }

Source/cmGlobalVisualStudio71Generator.h

@@ -33,7 +33,7 @@ protected:
     const std::string& platformMapping = "") override;
   void WriteExternalProject(std::ostream& fout, const std::string& name,
                             const char* path, const char* typeGuid,
-                            const std::set<std::string>& depends) override;
+                            const std::set<BT<std::string>>& depends) override;
   void WriteSLNHeader(std::ostream& fout) override;
 
   // Folders are not supported by VS 7.1.

Source/cmGlobalVisualStudio7Generator.h

@@ -145,7 +145,7 @@ protected:
 
   virtual void WriteExternalProject(
     std::ostream& fout, const std::string& name, const char* path,
-    const char* typeGuid, const std::set<std::string>& dependencies) = 0;
+    const char* typeGuid, const std::set<BT<std::string>>& dependencies) = 0;
 
   std::string ConvertToSolutionPath(const char* path);
 

Source/cmGlobalVisualStudio8Generator.cxx

@@ -315,9 +315,9 @@ bool cmGlobalVisualStudio8Generator::NeedLinkLibraryDependencies(
   cmGeneratorTarget* target)
 {
   // Look for utility dependencies that magically link.
-  for (std::string const& ui : target->GetUtilities()) {
+  for (BT<std::string> const& ui : target->GetUtilities()) {
     if (cmGeneratorTarget* depTarget =
-          target->GetLocalGenerator()->FindGeneratorTargetToUse(ui)) {
+          target->GetLocalGenerator()->FindGeneratorTargetToUse(ui.Value)) {
       if (depTarget->GetType() != cmStateEnums::INTERFACE_LIBRARY &&
           depTarget->GetProperty("EXTERNAL_MSPROJECT")) {
         // This utility dependency names an external .vcproj target.

Source/cmLocalUnixMakefileGenerator3.cxx

@@ -17,6 +17,7 @@
 #include "cmGeneratorTarget.h"
 #include "cmGlobalGenerator.h"
 #include "cmGlobalUnixMakefileGenerator3.h"
+#include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
 #include "cmMakefileTargetGenerator.h"
@@ -1546,8 +1547,10 @@ void cmLocalUnixMakefileGenerator3::WriteLocalAllRules(
       if (!text) {
         text = "Running external command ...";
       }
-      depends.insert(depends.end(), gt->GetUtilities().begin(),
-                     gt->GetUtilities().end());
+      depends.reserve(gt->GetUtilities().size());
+      for (BT<std::string> const& u : gt->GetUtilities()) {
+        depends.push_back(u.Value);
+      }
       this->AppendEcho(commands, text,
                        cmLocalUnixMakefileGenerator3::EchoGlobal);
 

Source/cmQtAutoGenInitializer.cxx

@@ -12,6 +12,7 @@
 #include "cmGeneratorTarget.h"
 #include "cmGlobalGenerator.h"
 #include "cmLinkItem.h"
+#include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
 #include "cmOutputConverter.h"
@@ -940,8 +941,8 @@ bool cmQtAutoGenInitializer::InitAutogenTarget()
       new cmGeneratorTarget(autogenTarget, localGen));
 
     // Forward origin utilities to autogen target
-    for (std::string const& depName : this->Target->Target->GetUtilities()) {
-      autogenTarget->AddUtility(depName, makefile);
+    for (BT<std::string> const& depName : this->Target->GetUtilities()) {
+      autogenTarget->AddUtility(depName.Value, makefile);
     }
     // Add additional autogen target dependencies to autogen target
     for (cmTarget* depTarget : this->AutogenTarget.DependTargets) {

Source/cmTarget.cxx

@@ -486,24 +486,10 @@ cmGlobalGenerator* cmTarget::GetGlobalGenerator() const
   return this->GetMakefile()->GetGlobalGenerator();
 }
 
-void cmTarget::AddUtility(const std::string& u, cmMakefile* makefile)
+void cmTarget::AddUtility(std::string const& u, cmMakefile* mf)
 {
-  if (this->Utilities.insert(u).second && makefile) {
-    this->UtilityBacktraces.insert(
-      std::make_pair(u, makefile->GetBacktrace()));
-  }
-}
-
-cmListFileBacktrace const* cmTarget::GetUtilityBacktrace(
-  const std::string& u) const
-{
-  std::map<std::string, cmListFileBacktrace>::const_iterator i =
-    this->UtilityBacktraces.find(u);
-  if (i == this->UtilityBacktraces.end()) {
-    return nullptr;
-  }
-
-  return &i->second;
+  BT<std::string> util(u, mf ? mf->GetBacktrace() : cmListFileBacktrace());
+  this->Utilities.insert(util);
 }
 
 cmListFileBacktrace const& cmTarget::GetBacktrace() const

Source/cmTarget.h

@@ -190,10 +190,12 @@ public:
    * name as would be specified to the ADD_EXECUTABLE or UTILITY_SOURCE
    * commands. It is not a full path nor does it have an extension.
    */
-  void AddUtility(const std::string& u, cmMakefile* makefile = nullptr);
+  void AddUtility(std::string const& u, cmMakefile* mf = nullptr);
   ///! Get the utilities used by this target
-  std::set<std::string> const& GetUtilities() const { return this->Utilities; }
-  cmListFileBacktrace const* GetUtilityBacktrace(const std::string& u) const;
+  std::set<BT<std::string>> const& GetUtilities() const
+  {
+    return this->Utilities;
+  }
 
   ///! Set/Get a property of this target file
   void SetProperty(const std::string& prop, const char* value);
@@ -307,8 +309,7 @@ private:
   bool IsGeneratorProvided;
   cmPropertyMap Properties;
   std::set<std::string> SystemIncludeDirectories;
-  std::set<std::string> Utilities;
-  std::map<std::string, cmListFileBacktrace> UtilityBacktraces;
+  std::set<BT<std::string>> Utilities;
   cmPolicies::PolicyMap PolicyMap;
   std::string Name;
   std::string InstallPath;