export: Fix TARGET_NAME lookup for out-of-dir linking

Improve the logic added by commit f0e67da061 (target_link_libraries: Fix
out-of-dir linking of a list of targets, 2020-01-14, v3.17.0-rc1~149^2)
to, while exporting targets, look up referenced target names in the
correct directory.

Source/cmExportFileGenerator.cxx

@@ -16,7 +16,6 @@
 #include "cmFileSet.h"
 #include "cmGeneratedFileStream.h"
 #include "cmGeneratorTarget.h"
-#include "cmGlobalGenerator.h"
 #include "cmLinkItem.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
@@ -607,10 +606,10 @@ void cmExportFileGenerator::GenerateInterfaceProperties(
 
 bool cmExportFileGenerator::AddTargetNamespace(
   std::string& input, cmGeneratorTarget const* target,
-  std::vector<std::string>& missingTargets)
+  cmLocalGenerator const* lg, std::vector<std::string>& missingTargets)
 {
   cmGeneratorTarget::TargetOrString resolved =
-    target->ResolveTargetReference(input);
+    target->ResolveTargetReference(input, lg);
 
   cmGeneratorTarget* tgt = resolved.Target;
   if (!tgt) {
@@ -640,8 +639,10 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpressions(
   std::string& input, cmGeneratorTarget const* target,
   std::vector<std::string>& missingTargets, FreeTargetsReplace replace)
 {
+  cmLocalGenerator const* lg = target->GetLocalGenerator();
   if (replace == NoReplaceFreeTargets) {
-    this->ResolveTargetsInGeneratorExpression(input, target, missingTargets);
+    this->ResolveTargetsInGeneratorExpression(input, target, lg,
+                                              missingTargets);
     return;
   }
   std::vector<std::string> parts;
@@ -650,13 +651,14 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpressions(
   std::string sep;
   input.clear();
   for (std::string& li : parts) {
-    if (cmHasLiteralPrefix(li, CMAKE_DIRECTORY_ID_SEP)) {
+    if (target->IsLinkLookupScope(li, lg)) {
       continue;
     }
     if (cmGeneratorExpression::Find(li) == std::string::npos) {
-      this->AddTargetNamespace(li, target, missingTargets);
+      this->AddTargetNamespace(li, target, lg, missingTargets);
     } else {
-      this->ResolveTargetsInGeneratorExpression(li, target, missingTargets);
+      this->ResolveTargetsInGeneratorExpression(li, target, lg,
+                                                missingTargets);
     }
     input += sep + li;
     sep = ";";
@@ -665,7 +667,7 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpressions(
 
 void cmExportFileGenerator::ResolveTargetsInGeneratorExpression(
   std::string& input, cmGeneratorTarget const* target,
-  std::vector<std::string>& missingTargets)
+  cmLocalGenerator const* lg, std::vector<std::string>& missingTargets)
 {
   std::string::size_type pos = 0;
   std::string::size_type lastPos = pos;
@@ -689,7 +691,7 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpression(
     std::string targetName =
       input.substr(nameStartPos, commaPos - nameStartPos);
 
-    if (this->AddTargetNamespace(targetName, target, missingTargets)) {
+    if (this->AddTargetNamespace(targetName, target, lg, missingTargets)) {
       input.replace(nameStartPos, commaPos - nameStartPos, targetName);
     }
     lastPos = nameStartPos + targetName.size() + 1;
@@ -711,7 +713,7 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpression(
                     "literal.";
       break;
     }
-    if (!this->AddTargetNamespace(targetName, target, missingTargets)) {
+    if (!this->AddTargetNamespace(targetName, target, lg, missingTargets)) {
       errorString = "$<TARGET_NAME:...> requires its parameter to be a "
                     "reachable target.";
       break;
@@ -732,7 +734,7 @@ void cmExportFileGenerator::ResolveTargetsInGeneratorExpression(
     }
     std::string libName = input.substr(nameStartPos, endPos - nameStartPos);
     if (cmGeneratorExpression::IsValidTargetName(libName) &&
-        this->AddTargetNamespace(libName, target, missingTargets)) {
+        this->AddTargetNamespace(libName, target, lg, missingTargets)) {
       input.replace(nameStartPos, endPos - nameStartPos, libName);
     }
     lastPos = nameStartPos + libName.size() + 1;
@@ -900,6 +902,8 @@ void cmExportFileGenerator::SetImportLinkProperty(
     return;
   }
 
+  cmLocalGenerator const* lg = target->GetLocalGenerator();
+
   // Construct the property value.
   std::string link_entries;
   const char* sep = "";
@@ -910,7 +914,7 @@ void cmExportFileGenerator::SetImportLinkProperty(
 
     if (targetNames == ImportLinkPropertyTargetNames::Yes) {
       std::string temp = asString(l);
-      this->AddTargetNamespace(temp, target, missingTargets);
+      this->AddTargetNamespace(temp, target, lg, missingTargets);
       link_entries += temp;
     } else {
       link_entries += asString(l);

Source/cmExportFileGenerator.h

@@ -17,6 +17,7 @@
 
 class cmFileSet;
 class cmGeneratorTarget;
+class cmLocalGenerator;
 class cmTargetExport;
 
 #define STRINGIFY_HELPER(X) #X
@@ -223,11 +224,12 @@ private:
                                  std::vector<std::string>& missingTargets);
 
   bool AddTargetNamespace(std::string& input, cmGeneratorTarget const* target,
+                          cmLocalGenerator const* lg,
                           std::vector<std::string>& missingTargets);
 
   void ResolveTargetsInGeneratorExpression(
     std::string& input, cmGeneratorTarget const* target,
-    std::vector<std::string>& missingTargets);
+    cmLocalGenerator const* lg, std::vector<std::string>& missingTargets);
 
   virtual void ReplaceInstallPrefix(std::string& input);
 

Source/cmGeneratorTarget.h

@@ -856,6 +856,9 @@ public:
   std::string GetFortranModuleDirectory(std::string const& working_dir) const;
   bool IsFortranBuildingInstrinsicModules() const;
 
+  bool IsLinkLookupScope(std::string const& n,
+                         cmLocalGenerator const*& lg) const;
+
   cmValue GetSourcesProperty() const;
 
   void AddISPCGeneratedHeader(std::string const& header,
@@ -1073,9 +1076,6 @@ private:
   std::unordered_map<std::string, std::vector<std::string>>
     ISPCGeneratedObjects;
 
-  bool IsLinkLookupScope(std::string const& n,
-                         cmLocalGenerator const*& lg) const;
-
   enum class LinkInterfaceField
   {
     Libraries,

Tests/ExportImport/Export/SubDirLinkA/CMakeLists.txt

@@ -1,6 +1,9 @@
 add_library(SubDirLinkAImported IMPORTED INTERFACE)
 target_compile_definitions(SubDirLinkAImported INTERFACE DEF_SubDirLinkAImportedForExport)
 
-target_link_libraries(TopDirLib PUBLIC debug "$<1:SubDirLinkAImported;SubDirLinkAImported>" optimized "$<1:SubDirLinkAImported;SubDirLinkAImported>")
+target_link_libraries(TopDirLib PUBLIC
+  debug "$<1:$<TARGET_NAME:SubDirLinkAImported>;$<TARGET_NAME:SubDirLinkAImported>>"
+  optimized "$<1:$<TARGET_NAME:SubDirLinkAImported>;$<TARGET_NAME:SubDirLinkAImported>>"
+)
 
 add_library(SubDirLinkA STATIC SubDirLinkA.c)