View Compilation Error

0_0_38523414_25345.cpp: In function 'constexpr int qpow(int, int)':
0_0_38523414_25345.cpp:22:1: error: body of constexpr function 'constexpr int qpow(int, int)' not a return-statement
 }
 ^
0_0_38523414_25345.cpp: At global scope:
0_0_38523414_25345.cpp:24:39: error: 'constexpr int qpow(int, int)' called in a constant expression
 constexpr int P = qpow(SQRT_5, MOD - 2);
                                       ^