cmComputeLinkInformation: use `cmStrCat` where appropriate

Source/cmComputeLinkInformation.cxx

@@ -289,28 +289,28 @@ cmComputeLinkInformation::cmComputeLinkInformation(
 
   // Get options needed to link libraries.
   if (cmValue flag = this->Makefile->GetDefinition(
-        "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_FLAG")) {
+        cmStrCat("CMAKE_", this->LinkLanguage, "_LINK_LIBRARY_FLAG"))) {
     this->LibLinkFlag = *flag;
   } else {
     this->LibLinkFlag =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_FLAG");
   }
   if (cmValue flag = this->Makefile->GetDefinition(
-        "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_FILE_FLAG")) {
+        cmStrCat("CMAKE_", this->LinkLanguage, "_LINK_LIBRARY_FILE_FLAG"))) {
     this->LibLinkFileFlag = *flag;
   } else {
     this->LibLinkFileFlag =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_FILE_FLAG");
   }
   if (cmValue suffix = this->Makefile->GetDefinition(
-        "CMAKE_" + this->LinkLanguage + "_LINK_LIBRARY_SUFFIX")) {
+        cmStrCat("CMAKE_", this->LinkLanguage, "_LINK_LIBRARY_SUFFIX"))) {
     this->LibLinkSuffix = *suffix;
   } else {
     this->LibLinkSuffix =
       this->Makefile->GetSafeDefinition("CMAKE_LINK_LIBRARY_SUFFIX");
   }
   if (cmValue flag = this->Makefile->GetDefinition(
-        "CMAKE_" + this->LinkLanguage + "_LINK_OBJECT_FILE_FLAG")) {
+        cmStrCat("CMAKE_", this->LinkLanguage, "_LINK_OBJECT_FILE_FLAG"))) {
     this->ObjLinkFileFlag = *flag;
   } else {
     this->ObjLinkFileFlag =
@@ -325,7 +325,7 @@ cmComputeLinkInformation::cmComputeLinkInformation(
                            : "SHARED_LIBRARY");
     std::string rtVar =
       cmStrCat("CMAKE_", tType, "_RUNTIME_", this->LinkLanguage, "_FLAG");
-    std::string rtSepVar = rtVar + "_SEP";
+    std::string rtSepVar = cmStrCat(rtVar, "_SEP");
     this->RuntimeFlag = this->Makefile->GetSafeDefinition(rtVar);
     this->RuntimeSep = this->Makefile->GetSafeDefinition(rtSepVar);
     this->RuntimeAlways = (this->Makefile->GetSafeDefinition(
@@ -1070,8 +1070,8 @@ void cmComputeLinkInformation::AddRuntimeLinkLibrary(std::string const& lang)
   if (runtimeLibrary.empty()) {
     return;
   }
-  if (cmValue runtimeLinkOptions = this->Makefile->GetDefinition(
-        "CMAKE_" + lang + "_RUNTIME_LIBRARY_LINK_OPTIONS_" + runtimeLibrary)) {
+  if (cmValue runtimeLinkOptions = this->Makefile->GetDefinition(cmStrCat(
+        "CMAKE_", lang, "_RUNTIME_LIBRARY_LINK_OPTIONS_", runtimeLibrary))) {
     std::vector<std::string> libsVec = cmExpandedList(*runtimeLinkOptions);
     for (std::string const& i : libsVec) {
       if (!cm::contains(this->ImplicitLinkLibs, i)) {
@@ -1697,7 +1697,8 @@ bool cmComputeLinkInformation::CheckImplicitDirItem(LinkEntry const& entry)
     case cmPolicies::WARN:
       if (this->CMP0060Warn) {
         // Print the warning at most once for this item.
-        std::string const& wid = "CMP0060-WARNING-GIVEN-" + item.Value;
+        std::string const& wid =
+          cmStrCat("CMP0060-WARNING-GIVEN-", item.Value);
         if (!this->CMakeInstance->GetPropertyAsBool(wid)) {
           this->CMakeInstance->SetProperty(wid, "1");
           this->CMP0060WarnItems.insert(item.Value);
@@ -2144,7 +2145,7 @@ void cmComputeLinkInformation::LoadImplicitLinkInfo()
   if (cmValue libraryArch =
         this->Makefile->GetDefinition("CMAKE_LIBRARY_ARCHITECTURE")) {
     for (std::string const& i : implicitDirVec) {
-      this->ImplicitLinkDirs.insert(i + "/" + *libraryArch);
+      this->ImplicitLinkDirs.insert(cmStrCat(i, '/', *libraryArch));
     }
   }
 
@@ -2400,10 +2401,11 @@ void cmComputeLinkInformation::GetRPath(std::vector<std::string>& runtimeDirs,
     cmGeneratorTarget::LinkClosure const* lc =
       this->Target->GetLinkClosure(this->Config);
     for (std::string const& li : lc->Languages) {
-      std::string useVar =
-        "CMAKE_" + li + "_USE_IMPLICIT_LINK_DIRECTORIES_IN_RUNTIME_PATH";
+      std::string useVar = cmStrCat(
+        "CMAKE_", li, "_USE_IMPLICIT_LINK_DIRECTORIES_IN_RUNTIME_PATH");
       if (this->Makefile->IsOn(useVar)) {
-        std::string dirVar = "CMAKE_" + li + "_IMPLICIT_LINK_DIRECTORIES";
+        std::string dirVar =
+          cmStrCat("CMAKE_", li, "_IMPLICIT_LINK_DIRECTORIES");
         if (cmValue dirs = this->Makefile->GetDefinition(dirVar)) {
           cmCLI_ExpandListUnique(*dirs, runtimeDirs, emitted);
         }