From fc13431939798fe7d61b8d57d56a939d5b8a0de9 Mon Sep 17 00:00:00 2001
From: Jeffrey Walton <noloader@gmail.com>
Date: Fri, 17 May 2019 04:17:44 -0400
Subject: [PATCH] Clear GCC unknown pragma warning

---
 nbtheory.cpp | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/nbtheory.cpp b/nbtheory.cpp
index de812374..310e6cb9 100644
--- a/nbtheory.cpp
+++ b/nbtheory.cpp
@@ -646,6 +646,7 @@ bool SolveModularQuadraticEquation(Integer &r1, Integer &r2, const Integer &a, c
 Integer ModularRoot(const Integer &a, const Integer &dp, const Integer &dq,
 					const Integer &p, const Integer &q, const Integer &u)
 {
+#ifdef _OPENMP
 	Integer p2, q2;
 	#pragma omp parallel
 		#pragma omp sections
@@ -655,6 +656,11 @@ Integer ModularRoot(const Integer &a, const Integer &dp, const Integer &dq,
 			#pragma omp section
 				q2 = ModularExponentiation((a % q), dq, q);
 		}
+#else
+	const Integer p2 = ModularExponentiation((a % p), dp, p);
+	const Integer q2 = ModularExponentiation((a % q), dq, q);
+#endif
+
 	return CRT(p2, p, q2, q, u);
 }
 
@@ -997,7 +1003,9 @@ Integer Lucas(const Integer &n, const Integer &P, const Integer &modulus)
 
 Integer InverseLucas(const Integer &e, const Integer &m, const Integer &p, const Integer &q, const Integer &u)
 {
-	Integer d = (m*m-4);
+	const Integer d = (m*m-4);
+
+#ifdef _OPENMP
 	Integer p2, q2;
 	#pragma omp parallel
 		#pragma omp sections
@@ -1013,6 +1021,14 @@ Integer InverseLucas(const Integer &e, const Integer &m, const Integer &p, const
 				q2 = Lucas(EuclideanMultiplicativeInverse(e,q2), m, q);
 			}
 		}
+#else
+	const Integer t1 = p-Jacobi(d,p);
+	const Integer p2 = Lucas(EuclideanMultiplicativeInverse(e,t1), m, p);
+
+	const Integer t2 = q-Jacobi(d,q);
+	const Integer q2 = Lucas(EuclideanMultiplicativeInverse(e,t2), m, q);
+#endif
+
 	return CRT(p2, p, q2, q, u);
 }