diff --git a/configure.ac b/configure.ac
index 6080109c35..87c6d5bf91 100644
--- a/configure.ac
+++ b/configure.ac
@@ -76,11 +76,26 @@ AM_CONDITIONAL([ENABLE_TESTS], [test "x$enable_tests" = xyes])
 AS_CASE([$host_cpu],
 	[*arm*], [host_cpu=arm],
 	[*amd64*], [host_cpu=x86_64 HOSTARCH=intel],
-	[i?86], [HOSTARCH=intel],
+	[i?86], [host_cpu=i386 HOSTARCH=intel],
+	[mipsel*], [host_cpu=mips],
+	[mips64el*], [host_cpu=mips64],
+	[powerpc*], [host_cpu=powerpc],
+	[ppc64*], [host_cpu=powerpc64],
 	[x86_64], [HOSTARCH=intel]
 )
 AM_CONDITIONAL([HOST_CPU_IS_INTEL], [test "x$HOSTARCH" = "xintel"])
 
+AM_CONDITIONAL([HOST_AARCH64],   [test "$host_cpu" = "aarch64"])
+AM_CONDITIONAL([HOST_ARM],       [test "$host_cpu" = "arm"])
+AM_CONDITIONAL([HOST_I386],      [test "$host_cpu" = "i386"])
+AM_CONDITIONAL([HOST_MIPS],      [test "$host_cpu" = "mips"])
+AM_CONDITIONAL([HOST_MIPS64],    [test "$host_cpu" = "mips64"])
+AM_CONDITIONAL([HOST_POWERPC],   [test "$host_cpu" = "powerpc"])
+AM_CONDITIONAL([HOST_POWERPC64], [test "$host_cpu" = "ppc64"])
+AM_CONDITIONAL([HOST_RISCV64],   [test "$host_cpu" = "riscv64"])
+AM_CONDITIONAL([HOST_SPARC64],   [test "$host_cpu" = "sparc64"])
+AM_CONDITIONAL([HOST_X86_64],    [test "$host_cpu" = "x86_64"])
+
 AC_MSG_CHECKING([if .gnu.warning accepts long strings])
 AC_LINK_IFELSE([AC_LANG_SOURCE([[
 extern void SSLv3_method();
diff --git a/crypto/Makefile.am b/crypto/Makefile.am
index 09a22e6502..733dcbdf36 100644
--- a/crypto/Makefile.am
+++ b/crypto/Makefile.am
@@ -445,20 +445,51 @@ noinst_HEADERS += bn/s2n_bignum.h
 noinst_HEADERS += bn/s2n_bignum_internal.h
 
 # bn/arch
+if HOST_AARCH64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/aarch64/
+endif
 noinst_HEADERS += bn/arch/aarch64/bn_arch.h
-noinst_HEADERS += bn/arch/alpha/bn_arch.h
-noinst_HEADERS += bn/arch/amd64/bn_arch.h
+
+if HOST_ARM
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/arm/
+endif
 noinst_HEADERS += bn/arch/arm/bn_arch.h
-noinst_HEADERS += bn/arch/hppa/bn_arch.h
+
+if HOST_I386
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/i386/
+endif
 noinst_HEADERS += bn/arch/i386/bn_arch.h
-noinst_HEADERS += bn/arch/m88k/bn_arch.h
+
+if HOST_MIPS64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/mips64/
+endif
 noinst_HEADERS += bn/arch/mips64/bn_arch.h
+
+if HOST_POWERPC
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/powerpc/
+endif
 noinst_HEADERS += bn/arch/powerpc/bn_arch.h
+
+if HOST_POWERPC64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/powerpc64/
+endif
 noinst_HEADERS += bn/arch/powerpc64/bn_arch.h
+
+if HOST_RISCV64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/riscv64/
+endif
 noinst_HEADERS += bn/arch/riscv64/bn_arch.h
-noinst_HEADERS += bn/arch/sh/bn_arch.h
+
+if HOST_SPARC64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/sparc64/
+endif
 noinst_HEADERS += bn/arch/sparc64/bn_arch.h
 
+if HOST_X86_64
+libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/amd64/
+endif
+noinst_HEADERS += bn/arch/amd64/bn_arch.h
+
 # buffer
 libcrypto_la_SOURCES += buffer/buf_err.c
 libcrypto_la_SOURCES += buffer/buf_str.c
diff --git a/crypto/Makefile.am.elf-x86_64 b/crypto/Makefile.am.elf-x86_64
index f03d424bbe..cc6ea99c9d 100644
--- a/crypto/Makefile.am.elf-x86_64
+++ b/crypto/Makefile.am.elf-x86_64
@@ -50,7 +50,4 @@ libcrypto_la_CPPFLAGS += -DSHA512_ASM
 libcrypto_la_CPPFLAGS += -DWHIRLPOOL_ASM
 libcrypto_la_CPPFLAGS += -DOPENSSL_CPUID_OBJ
 libcrypto_la_SOURCES += $(ASM_X86_64_ELF)
-
-# XXX - not the right place for this. It should be done depending on CPU.
-libcrypto_la_CPPFLAGS += -I$(top_srcdir)/crypto/bn/arch/amd64/
 endif