diff --git a/graphics/s2/files/patch-src_s2_util_math_exactfloat_exactfloat.cc b/graphics/s2/files/patch-src_s2_util_math_exactfloat_exactfloat.cc
new file mode 100644
index 000000000000..fd6dfaec318c
--- /dev/null
+++ b/graphics/s2/files/patch-src_s2_util_math_exactfloat_exactfloat.cc
@@ -0,0 +1,11 @@
+--- src/s2/util/math/exactfloat/exactfloat.cc.orig	2022-05-24 22:12:24 UTC
++++ src/s2/util/math/exactfloat/exactfloat.cc
+@@ -141,7 +141,7 @@ inline static uint64 BN_ext_get_uint64(const BIGNUM* b
+ #ifdef IS_LITTLE_ENDIAN
+   S2_CHECK_EQ(BN_bn2lebinpad(bn, reinterpret_cast<unsigned char*>(&r),
+               sizeof(r)), sizeof(r));
+-#elif IS_BIG_ENDIAN
++#elif defined(IS_BIG_ENDIAN)
+   S2_CHECK_EQ(BN_bn2binpad(bn, reinterpret_cast<unsigned char*>(&r),
+               sizeof(r)), sizeof(r));
+ #else