#5717 Segmentation fault when providing multiple --include=/path/to/header arguments.

lib/preprocessor.cpp

@@ -2283,7 +2283,7 @@ void Preprocessor::handleIncludes(std::string &code, const std::string &filePath
 
         // If endfile is encountered, we have moved to a next file in our stack,
         // so remove last path in our list.
-        while ((endfilePos = code.find("\n#endfile", endfilePos)) != std::string::npos && endfilePos < pos) {
+        while (!paths.empty() && (endfilePos = code.find("\n#endfile", endfilePos)) != std::string::npos && endfilePos < pos) {
             paths.pop_back();
             endfilePos += 9; // size of #endfile
         }

test/testpreprocessor.cpp

@@ -300,6 +300,8 @@ private:
         TEST_CASE(validateCfg);
 
         TEST_CASE(if_sizeof);
+
+        TEST_CASE(double_include); // #5717
     }
 
 
@@ -4021,6 +4023,18 @@ private:
         preprocessor.preprocess(istr, actual, "file.c");
         ASSERT_EQUALS("\nFred & Wilma\n\n\n\n\n", actual[""]);
     }
+
+    void double_include() {
+        const char code[] = "int x";
+
+        Preprocessor preprocessor(nullptr, this);
+        std::list<std::string> includePaths;
+        includePaths.push_back(".");
+        includePaths.push_back(".");
+        std::map<std::string,std::string> defs;
+        std::set<std::string> pragmaOnce;
+        preprocessor.handleIncludes(code, "123.h", includePaths, defs, pragmaOnce, std::list<std::string>());
+    }
 };
 
 REGISTER_TEST(TestPreprocessor)