Compiler Error C2017

illegal escape sequence

An escape sequence, such as \t, appears outside of a character or string constant.

The following sample generates C2017:

// C2017.cpp
int main() {
   char test1='a'\n;   // C2017
   char test2='a\n';   // ok
}

C2017 can occur when the stringize operator is used with strings that include escape sequences.

The following sample generates C2017:

// C2017b.cpp
#define TestDfn(x) AfxMessageBox(#x)
TestDfn(CString("\\") + CString(".h\"\n\n"));   // C2017