[LyX/master] Add comment

[Scott Kostyshak]

commit 6f207b37ed295447658677cad3b962efd7e3c028
Author: Scott Kostyshak <skost...@lyx.org>
Date:   Wed Nov 18 21:33:44 2015 -0500

    Add comment

diff --git a/src/LaTeX.cpp b/src/LaTeX.cpp
index 4278a35..e6a185c 100644
--- a/src/LaTeX.cpp
+++ b/src/LaTeX.cpp
@@ -407,8 +407,12 @@ int LaTeX::run(TeXErrors & terr)
        // Write the dependencies to file.
        head.write(depfile);
 
-       if (exit_code)
+       if (exit_code) {
+               // add flag here, just before return, instead of when exit_code
+               // is defined because scanres is sometimes overwritten above
+               // (e.g. rerun)
                scanres |= NONZERO_ERROR;
+       }
 
        LYXERR(Debug::LATEX, "Done.");