Add version and build of cppfront to generated files. (hsutter#791)

* Add version and build of cppfront to generated files.

* Add a flag to control the information

* Add version and build of cppfront to generated files.

* Cherry-Picked: Add a flag to control the information
by Herb Sutter

* Added missed file.

---------

Signed-off-by: Herb Sutter <herb.sutter@gmail.com>
Co-authored-by: Ingo Prötel <ingo.proetel@macio.de>
Co-authored-by: Herb Sutter <herb.sutter@gmail.com>
Co-authored-by: Ingo Prötel <git@iprtel.de>

source/common.h

@@ -821,7 +821,9 @@ class cmdline_processor
         -> void
     {
         help_requested = true;
-        print("\ncppfront compiler v0.3.0   Build "
+        print("\ncppfront compiler "
+            #include "version.info"
+        "   Build "
             #include "build.info"
         );
         print("\nCopyright(c) Herb Sutter   All rights reserved\n");

source/to_cpp1.h

@@ -63,6 +63,14 @@ auto pad(int padding)
 //
 //-----------------------------------------------------------------------
 //
+static auto flag_emit_cppfront_info = false;
+static cmdline_processor::register_flag cmd_emit_cppfront_info(
+    9,
+    "emit-cppfront-info",
+    "Emit cppfront version/build in output file",
+    []{ flag_emit_cppfront_info = true; }
+);
+
 static auto flag_clean_cpp1 = false;
 static cmdline_processor::register_flag cmd_clean_cpp1(
     9,
@@ -1289,6 +1297,14 @@ class cppfront
             || flag_include_std
             )
         {
+            if (flag_emit_cppfront_info) {
+                printer.print_extra(
+                    "\n// Generated by cppfront "
+                    #include "version.info"
+                    " build " 
+                    #include "build.info"
+                );
+            }
             printer.print_extra( "\n" );
             if (cpp1_filename.back() == 'h') {
                 printer.print_extra( "#ifndef " + cpp1_FILENAME+"_CPP2\n");

source/version.info

@@ -0,0 +1 @@
+"v0.3.0"