wheel: add a target for amdx86_64-musl wheels

These can be installed on alpine… which is quite useful.

Makefile

@@ -226,6 +226,7 b' packaging_targets := \\'
   fedora \
   linux-wheels \
   linux-wheels-x86_64 \
+  linux-wheels-x86_64-musl \
   linux-wheels-i686 \
   ppa
 

contrib/packaging/Makefile

@@ -45,8 +45,10 b' help:'
 	@echo 'linux-wheels'
 	@echo '   Build Linux manylinux wheels using Docker.'
 	@echo ''
-	@echo 'linux-wheels-{x86_64, i686}'
+	@echo 'linux-wheels-{x86_64, i686}{,-musl}'
 	@echo '   Build Linux manylinux wheels for a specific architecture using Docker'
+	@echo '   The -musl variants is suitable for system using "musl" instead of "glibc",
+	@echo '   for example: Alpine linux.'
 	@echo ''
 	@echo 'deb'
 	@echo '   Build a Debian package locally targeting the current system'
@@ -125,8 +127,7 b' endef'
 $(foreach release,$(RHEL_RELEASES),$(eval $(call rhel_targets,$(release))))
 
 .PHONY: linux-wheels
-linux-wheels: linux-wheels-x86_64
-
+linux-wheels: linux-wheels-x86_64 linux-wheels-x86_64-musl
 
 img_reg="registry.heptapod.net/mercurial/ci-images"
 img_tag="v3.0"
@@ -136,6 +137,10 b' whl_sh="/src/contrib/packaging/build-lin'
 linux-wheels-x86_64:
 	docker run --rm -ti -v `pwd`/../..:/src $(img_reg)/core-wheel-x86_64-c:$(img_tag) $(whl_sh)
 
+.PHONY: linux-wheels-x86_64-musl
+linux-wheels-x86_64-musl:
+	docker run --rm -ti -v `pwd`/../..:/src $(img_reg)/core-wheel-x86_64-musl-c:$(img_tag) $(whl_sh)
+
 .PHONY: linux-wheels-i686
 linux-wheels-i686:
 	docker run -e "HGTEST_JOBS=$(shell nproc)" --rm -ti -v `pwd`/../..:/src quay.io/pypa/manylinux1_i686 linux32 /src/contrib/packaging/build-linux-wheels.sh