debian/changelog

+lambda-align2 (2.0.0-2) unstable; urgency=medium
+
+  * Enable verbose mode in d/rules.
+  * Only activate multiopt builds on archs that support the required
+    compiler flags.
+
+ -- Sascha Steinbiss <satta@debian.org>  Sat, 19 Jan 2019 23:19:18 +0100
+
 lambda-align2 (2.0.0-1) unstable; urgency=medium
 
   * Initial packaging for 2.x series (Closes: #919726)

debian/rules

 #!/usr/bin/make -f
 
 export DEB_BUILD_MAINT_OPTIONS = hardening=+all
+export DH_VERBOSE=1
+
 include /usr/share/dpkg/pkg-info.mk
+include /usr/share/dpkg/architecture.mk
+
+MULTIOPT_ARCHS = amd64 kfreebsd-amd64
+
+ifneq (,$(findstring $(DEB_HOST_ARCH),$(MULTIOPT_ARCHS)))
+	ENABLE_MULTIOPT="-DLAMBDA_MULTIOPT_BUILD=1"
+else
+	ENABLE_MULTIOPT="-DLAMBDA_MULTIOPT_BUILD=0"
+endif
 
 %:
 	dh $@ --builddirectory=build
@@ -15,7 +26,7 @@ override_dh_auto_configure:
 		-DLAMBDA_NATIVE_BUILD=OFF \
 		-DLAMBDA_MMAPPED_DB=OFF \
 		-DCMAKE_BUILD_TYPE=Release \
-		-DLAMBDA_MULTIOPT_BUILD=1 \
+		$(ENABLE_MULTIOPT) \
 		-DLAMBDA_COMPILE_THREADS=$(shell nproc)
 
 override_dh_auto_test: