Genex: Fix COMPILE_LANGUAGE propagation through try_compile

When evaluating include directories during export to a `try_compile`
test project, thread the compile language through to the generator
expression evaluator so it can support `$<COMPILE_LANGUAGE:...>`.

Issue: #17811

1 files changed, 12 insertions, 7 deletions

diff --git a/Source/cmExportTryCompileFileGenerator.cxx b/Source/cmExportTryCompileFileGenerator.cxx
index 1fb9cf8..ae8cd37 100644
--- a/Source/cmExportTryCompileFileGenerator.cxx
+++ b/Source/cmExportTryCompileFileGenerator.cxx
@@ -18,7 +18,8 @@
 
 cmExportTryCompileFileGenerator::cmExportTryCompileFileGenerator(
   cmGlobalGenerator* gg, const std::vector<std::string>& targets,
-  cmMakefile* mf)
+  cmMakefile* mf, std::set<std::string> const& langs)
+  : Languages(langs.begin(), langs.end())
 {
   gg->CreateImportedGenerationObjects(mf, targets, this->Exports);
 }
@@ -36,12 +37,14 @@ bool cmExportTryCompileFileGenerator::GenerateMainFile(std::ostream& os)
 
       ImportPropertyMap properties;
 
+      for (std::string const& lang : this->Languages) {
 #define FIND_TARGETS(PROPERTY)                                                \
-  this->FindTargets("INTERFACE_" #PROPERTY, te, emittedDeps);
+  this->FindTargets("INTERFACE_" #PROPERTY, te, lang, emittedDeps);
 
-      CM_FOR_EACH_TRANSITIVE_PROPERTY_NAME(FIND_TARGETS)
+        CM_FOR_EACH_TRANSITIVE_PROPERTY_NAME(FIND_TARGETS)
 
 #undef FIND_TARGETS
+      }
 
       this->PopulateProperties(te, properties, emittedDeps);
 
@@ -53,7 +56,7 @@ bool cmExportTryCompileFileGenerator::GenerateMainFile(std::ostream& os)
 
 std::string cmExportTryCompileFileGenerator::FindTargets(
   const std::string& propName, cmGeneratorTarget const* tgt,
-  std::set<cmGeneratorTarget const*>& emitted)
+  std::string const& language, std::set<cmGeneratorTarget const*>& emitted)
 {
   const char* prop = tgt->GetProperty(propName);
   if (!prop) {
@@ -72,8 +75,9 @@ std::string cmExportTryCompileFileGenerator::FindTargets(
 
   cmGeneratorTarget gDummyHead(&dummyHead, tgt->GetLocalGenerator());
 
-  std::string result = cge->Evaluate(tgt->GetLocalGenerator(), this->Config,
-                                     false, &gDummyHead, tgt, &dagChecker);
+  std::string result =
+    cge->Evaluate(tgt->GetLocalGenerator(), this->Config, false, &gDummyHead,
+                  tgt, &dagChecker, language);
 
   const std::set<cmGeneratorTarget const*>& allTargets =
     cge->GetAllTargetsSeen();
@@ -97,7 +101,8 @@ void cmExportTryCompileFileGenerator::PopulateProperties(
     if (p.find("IMPORTED_LINK_INTERFACE_LIBRARIES") == 0 ||
         p.find("IMPORTED_LINK_DEPENDENT_LIBRARIES") == 0 ||
         p.find("INTERFACE_LINK_LIBRARIES") == 0) {
-      std::string evalResult = this->FindTargets(p, target, emitted);
+      std::string evalResult =
+        this->FindTargets(p, target, std::string(), emitted);
 
       std::vector<std::string> depends;
       cmSystemTools::ExpandListArgument(evalResult, depends);