NMake: Detect nmake version

Run `nmake -?` and extract the version from its output.
Use a timeout because Watcom tools come with a `nmake` tool
that always waits for user input on `-?`.

1 files changed, 3 insertions, 0 deletions

diff --git a/Source/cmGlobalNMakeMakefileGenerator.h b/Source/cmGlobalNMakeMakefileGenerator.h
index abe64ff963..c23eef8141 100644
--- a/Source/cmGlobalNMakeMakefileGenerator.h
+++ b/Source/cmGlobalNMakeMakefileGenerator.h
@@ -55,6 +55,9 @@ protected:
   void PrintBuildCommandAdvice(std::ostream& os, int jobs) const override;
 
 private:
+  std::string NMakeVersion;
+  bool FindMakeProgram(cmMakefile* mf) override;
+
   void PrintCompilerAdvice(std::ostream& os, std::string const& lang,
                            const char* envVar) const override;
 };