diff --git a/geo/pdal/patches/patch-vendor_eigen_Eigen_src_Core_util_ConfigureVectorization_h b/geo/pdal/patches/patch-vendor_eigen_Eigen_src_Core_util_ConfigureVectorization_h
new file mode 100644
index 00000000000..23742041938
--- /dev/null
+++ b/geo/pdal/patches/patch-vendor_eigen_Eigen_src_Core_util_ConfigureVectorization_h
@@ -0,0 +1,16 @@
+$OpenBSD: patch-vendor_eigen_Eigen_src_Core_util_ConfigureVectorization_h,v 1.1 2021/06/27 13:34:27 jasper Exp $
+
+Disable AltiVec for it breaks the build due to various undefined symbols (vec_sqrt, etc)
+
+Index: vendor/eigen/Eigen/src/Core/util/ConfigureVectorization.h
+--- vendor/eigen/Eigen/src/Core/util/ConfigureVectorization.h.orig
++++ vendor/eigen/Eigen/src/Core/util/ConfigureVectorization.h
+@@ -373,7 +373,7 @@
+     #undef vector
+     #undef pixel
+ 
+-  #elif defined __ALTIVEC__
++  #elif defined __ALTIVEC__ && !defined(__OpenBSD__)
+ 
+     #define EIGEN_VECTORIZE
+     #define EIGEN_VECTORIZE_ALTIVEC