diff --git a/dep/xxhash/CMakeLists.txt b/dep/xxhash/CMakeLists.txt
index bee7de896..6383188cc 100644
--- a/dep/xxhash/CMakeLists.txt
+++ b/dep/xxhash/CMakeLists.txt
@@ -6,6 +6,8 @@ set(SRCS
 add_library(xxhash ${SRCS})
 
 if(${CPU_ARCH} STREQUAL "x86" OR ${CPU_ARCH} STREQUAL "x64")
+  # Required if building with -mavx or -march=native, but you shouldn't be building with it.
+  target_compile_definitions(xxhash PRIVATE "XXH_X86DISPATCH_ALLOW_AVX")
   target_sources(xxhash PRIVATE
     include/xxh_x86dispatch.h
     src/xxh_x86dispatch.c