From 6f2f9ce331179091c6d5c75d78cdf3f67255ded1 Mon Sep 17 00:00:00 2001
From: Sebastian Holtermann <sebholt@xwmw.org>
Date: Fri, 9 Mar 2018 09:40:59 +0100
Subject: Autogen: Fix for the empty source file crash in 3.10.2

Issue: #17793
---
 Source/cmQtAutoGenerators.cxx | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/Source/cmQtAutoGenerators.cxx b/Source/cmQtAutoGenerators.cxx
index a9c9b9d..f91ebb2 100644
--- a/Source/cmQtAutoGenerators.cxx
+++ b/Source/cmQtAutoGenerators.cxx
@@ -80,15 +80,21 @@ static bool ReadFile(std::string& content, std::string const& filename,
     std::size_t const length = cmSystemTools::FileLength(filename);
     cmsys::ifstream ifs(filename.c_str(), (std::ios::in | std::ios::binary));
     if (ifs) {
-      content.resize(length);
-      ifs.read(&content.front(), content.size());
-      if (ifs) {
-        success = true;
+      if (length > 0) {
+        content.resize(length);
+        ifs.read(&content.front(), content.size());
+        if (ifs) {
+          success = true;
+        } else {
+          content.clear();
+          if (error != nullptr) {
+            error->append("Reading from the file failed.");
+          }
+        }
       } else {
+        // Readable but empty file
         content.clear();
-        if (error != nullptr) {
-          error->append("Reading from the file failed.");
-        }
+        success = true;
       }
     } else if (error != nullptr) {
       error->append("Opening the file for reading failed.");
-- 
cgit v0.12