diff --git a/math/primecount/files/patch-include_SieveTables.hpp b/math/primecount/files/patch-include_SieveTables.hpp
new file mode 100644
index 000000000000..4dd773f4b179
--- /dev/null
+++ b/math/primecount/files/patch-include_SieveTables.hpp
@@ -0,0 +1,29 @@
+--- include/SieveTables.hpp.orig	2021-12-20 20:37:55 UTC
++++ include/SieveTables.hpp
+@@ -60,22 +60,22 @@ constexpr int right_shift(int n)
+ /// on big endian CPU architectures.
+ 
+ /// Reverse byte order of 64-bit integer
+-constexpr uint64_t bswap64(uint64_t i, uint64_t j = 0, uint64_t n = 0)
++constexpr uint64_t bswap_64(uint64_t i, uint64_t j = 0, uint64_t n = 0)
+ {
+   return (n == sizeof(uint64_t)) ? j :
+-    bswap64(i >> 8, (j << 8) | (i & 0xff), n + 1);
++    bswap_64(i >> 8, (j << 8) | (i & 0xff), n + 1);
+ }
+ 
+ /// Bitmask to unset bits <= n
+ constexpr uint64_t unset_s(int n)
+ {
+-  return bswap64(~0ull << left_shift(n));
++  return bswap_64(~0ull << left_shift(n));
+ }
+ 
+ /// Bitmask to unset bits >= n
+ constexpr uint64_t unset_l(int n)
+ {
+-  return bswap64((n == 0) ? 0 : ~0ull >> right_shift(n));
++  return bswap_64((n == 0) ? 0 : ~0ull >> right_shift(n));
+ }
+ 
+ #else