Genex: Only evaluate TARGET_OBJECTS to determine target sources.

The output of this expression may contain macros for IDEs to replace
such as $(Configuration), $(CURRENT_ARCH) etc.  To avoid generating
content which is not usable in other contexts, report an error if
there is an attempt to use it in other contexts.

This commit may be reverted in the future if a solution to the
above difference is implemented.

1 files changed, 3 insertions, 1 deletions

diff --git a/Source/cmGeneratorExpression.cxx b/Source/cmGeneratorExpression.cxx
index e127f3a..d09e950 100644
--- a/Source/cmGeneratorExpression.cxx
+++ b/Source/cmGeneratorExpression.cxx
@@ -90,6 +90,7 @@ const char *cmCompiledGeneratorExpression::Evaluate(
   context.HadError = false;
   context.HadContextSensitiveCondition = false;
   context.HeadTarget = headTarget;
+  context.EvaluateForBuildsystem = this->EvaluateForBuildsystem;
   context.CurrentTarget = currentTarget ? currentTarget : headTarget;
   context.Backtrace = this->Backtrace;
 
@@ -124,7 +125,8 @@ cmCompiledGeneratorExpression::cmCompiledGeneratorExpression(
               cmListFileBacktrace const& backtrace,
               const std::string& input)
   : Backtrace(backtrace), Input(input),
-    HadContextSensitiveCondition(false)
+    HadContextSensitiveCondition(false),
+    EvaluateForBuildsystem(false)
 {
   cmGeneratorExpressionLexer l;
   std::vector<cmGeneratorExpressionToken> tokens =