silence flood of -Wunused-label warnings on s390x

ghc-8.4.3-warnings.mk-test.patch

@@ -0,0 +1,12 @@
+--- ghc-8.4.3/mk/warnings.mk~	2018-02-04 02:30:11.000000000 +0900
++++ ghc-8.4.3/mk/warnings.mk	2018-09-29 14:33:37.607884921 +0900
+@@ -1,6 +1,6 @@
+ # See Note [Order of warning flags].
+-SRC_CC_OPTS     += -Wall $(WERROR)
++#SRC_CC_OPTS     += -Wall $(WERROR)
+ SRC_HC_OPTS     += -Wall
+ # Don't add -Werror to SRC_HC_OPTS_STAGE0 (or SRC_HC_OPTS), because otherwise
+ # validate may unnecessarily fail when booting with an older compiler.
+ # It would be better to only exclude certain warnings from becoming errors
+
+Diff finished.  Sat Sep 29 14:35:43 2018

ghc.spec

@@ -45,6 +45,9 @@ Patch5:  ghc-configure-fix-sphinx-version-check.patch
 
 Patch12: ghc-armv7-VFPv3D16--NEON.patch
 
+# for s390x
+Patch15: ghc-8.4.3-warnings.mk-test.patch
+
 # Debian patches:
 Patch24: buildpath-abi-stability.patch
 Patch26: no-missing-haddock-file-warning.patch
@@ -260,6 +263,10 @@ rm -r libffi-tarballs
 %patch12 -p1 -b .orig
 %endif
 
+%ifarch s390x
+%patch15 -p1 -b .orig
+%endif
+
 %patch24 -p1 -b .orig
 %patch26 -p1 -b .orig
 #%%patch27 -p1 -b .orig
@@ -615,6 +622,7 @@ fi
 - drop bootstrap builds
 - no longer need autotools on aarch64
 - add armv7l to llvm-targets (patch from OpenSuse/Debian)
+- s390x: silence flood of -Wunused-label warnings
 
 * Mon Apr 30 2018 Jens Petersen <petersen@redhat.com> - 8.4.2-70.6
 - 8.4.2 perf build