Fixed #4351 (Escaped whitespace gives wrong error)

lib/preprocessor.cpp

@@ -153,9 +153,11 @@ std::string Preprocessor::read(std::istream &istr, const std::string &filename)
         if (ch == '\\') {
             unsigned char chNext;
 
+            unsigned int spaces = 0;
+
 #ifdef __GNUC__
             // gcc-compatibility: ignore spaces
-            for (;;) {
+            for (;; spaces++) {
                 chNext = (unsigned char)istr.peek();
                 if (chNext != '\n' && chNext != '\r' &&
                     (std::isspace(chNext) || std::iscntrl(chNext))) {
@@ -174,7 +176,7 @@ std::string Preprocessor::read(std::istream &istr, const std::string &filename)
                 ++newlines;
                 (void)readChar(istr,bom);   // Skip the "<backslash><newline>"
             } else
-                code << "\\";
+                code << "\\" << (spaces?" ":"");
         } else {
             code << char(ch);
 

test/testpreprocessor.cpp

@@ -68,6 +68,7 @@ private:
         TEST_CASE(readCode1);
         TEST_CASE(readCode2); // #4308 - convert C++11 raw string to plain old C string
         TEST_CASE(readCode3);
+        TEST_CASE(readCode4); // #4351 - escaped whitespace in gcc
 
         // reading utf-16 file
         TEST_CASE(utf16);
@@ -315,6 +316,15 @@ private:
         ASSERT_EQUALS("func(#errorname)", codestr);
     }
 
+    void readCode4() {
+        const char code[] = "char c = '\\ ';";
+        Settings settings;
+        Preprocessor preprocessor(&settings, this);
+        std::istringstream istr(code);
+        ASSERT_EQUALS("char c = '\\ ';", preprocessor.read(istr,"test.c"));
+        ASSERT_EQUALS("", errout.str());
+    }
+
 
     void utf16() {
         Settings settings;