diff --git a/configure.ac b/configure.ac
index 8cb7fd1b3f09819b7c8b57ce5d70e3b38e32a637..c7cc7e359863657bf48fc67db40558a354edc5b2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -455,8 +455,9 @@ if test "$ac_cv_header_fftw3_h" = "yes"; then
 fi
 AC_SUBST([FFTW_LIBS])
 
-# Check for Intel intrinsics header optionally used by vector.h.
+# Check for Intel and PowerPC intrinsics header optionally used by vector.h.
 AC_CHECK_HEADERS([immintrin.h])
+AC_CHECK_HEADERS([altivec.h])
 
 # Check for timing functions needed by cycle.h.
 AC_HEADER_TIME