<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/57060>57060</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Error thrown while compiling lib/Transforms/Scalar/FPG.cpp with clang++
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          BalaRishi-AMD
      </td>
    </tr>
</table>

<pre>
    
The below error is faced while building llvm (during compilation of llvm-project/llvm/lib/Transforms/Scalar/FPG.cpp) using llvm:
/home/amd/llvm-project/llvm/lib/Transforms/Scalar/FPG.cpp:1991:88: error: expected '{' after '\N' escape sequence

This issue was **introduced between 2022-06-21 and 2022-06-30.**


Reduced issue reproducer is given below:

_$ cat hello.cpp_
#include <iostream>
int main() {
    std::cout << "Hello \N \n";
    return 0;
}

_$ $compilerspath/DT2022_06_21/bin/clang++  hello.cpp  && ./a.out_
hello.cpp:3:25: warning: unknown escape sequence '\N' [-Wunknown-escape-sequence]
    std::cout << "Hello \N \n";
                        ^~
1 warning generated.
Hello N

## The above is older llvm build. The below is a recent one

_$ $compilerspath/DT2022_06_30/bin/clang++  hello.cpp  && ./a.out_
**hello.cpp:3:25: error: expected '{' after '\N' escape sequence**
    std::cout << "Hello \N \n";
                        ^~
1 error generated.
</pre>
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