From eedc4049fe1f69f9326b6ea4310a1d3d7ab8e0d2 Mon Sep 17 00:00:00 2001
From: Ximin Luo <infinity0@debian.org>
Date: Mon, 1 May 2017 20:40:30 +0200
Subject: [PATCH] Add support for cross-compiling, use stable release channel

---
 debian/control |  4 +++-
 debian/rules   | 29 ++++++++++++++++++++++++-----
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/debian/control b/debian/control
index 05612b4cd..4d89cba47 100644
--- a/debian/control
+++ b/debian/control
@@ -10,12 +10,14 @@ Build-Depends: debhelper (>= 9.20141010),
                rustc (>= 1.16),
                pkg-config,
                cmake,
-               cargo (>= 0.7.0) <!pkg.cargo.mkstage0>,
+               cargo (>= 0.13.0) <!pkg.cargo.mkstage0>,
                python-dulwich <pkg.cargo.mkstage0>,
                python-pytoml <pkg.cargo.mkstage0>,
                ca-certificates,
                bash-completion,
                libcurl4-gnutls-dev | libcurl4-openssl-dev,
+# Direct dependency needed for cross-compiling
+               libstd-rust-dev,
                libssh2-1-dev,
                libgit2-dev (>= 0.25.1),
                libhttp-parser-dev,
diff --git a/debian/rules b/debian/rules
index e398a8a21..8173942b2 100755
--- a/debian/rules
+++ b/debian/rules
@@ -5,6 +5,12 @@ include /usr/share/dpkg/architecture.mk
 include /usr/share/dpkg/buildflags.mk
 include /usr/share/rustc/architecture.mk
 
+# For cross-compiling; perhaps we should add this to dh-cargo or debcargo
+export PKG_CONFIG = $(DEB_HOST_GNU_TYPE)-pkg-config
+export PKG_CONFIG_ALLOW_CROSS = 1
+RUSTFLAGS += -C linker=$(DEB_HOST_GNU_TYPE)-gcc
+
+# Pass on dpkg-buildflags stuff
 RUSTFLAGS += $(foreach flag,$(LDFLAGS),-C link-arg=$(flag))
 export CFLAGS CXXFLAGS CPPFLAGS LDFLAGS RUSTFLAGS
 
@@ -21,7 +27,7 @@ override_dh_auto_configure:
 ifneq ($(filter pkg.cargo.mkstage0,$(DEB_BUILD_PROFILES)),)
 	# NOTE: this very likely doesn't work any more, see bootstrap.py for details
 	# Instead, you can try to bootstrap by setting PATH to a binary cargo
-	# downloaded from upstream, or by (TODO) cross-compiling.
+	# downloaded from upstream; or by cross-compiling, see "build-cross" below
 	# Preserved in case someone wants to resurrect it later:
 	# Bootstrap cargo stage0
 	./debian/bootstrap.py \
@@ -45,11 +51,16 @@ endif
 		--disable-debug \
 		--enable-optimize \
 		--local-rust-root=/usr \
-		--cargo=$(CURDIR)/cargo-stage0
+		--release-channel=stable \
+		--cargo=$(CURDIR)/cargo-stage0 \
+		--build=$(DEB_BUILD_RUST_TYPE) \
+		--host=$(DEB_HOST_RUST_TYPE) \
+		--target=$(DEB_TARGET_RUST_TYPE)
 
-override_dh_auto_build:
-	# Build final cargo binary and docs
-	$(MAKE)
+override_dh_auto_build-arch:
+	RUST_BACKTRACE=1 $(MAKE)
+
+override_dh_auto_build-indep:
 ifeq (,$(findstring nodoc,$(DEB_BUILD_PROFILES)))
 	$(MAKE) doc
 	cd target/doc/ && rm -f jquery.js && ln -s /usr/share/javascript/jquery/jquery.js
@@ -70,3 +81,11 @@ override_dh_auto_clean:
 			$(CURDIR)/config.stamp \
 			$(CURDIR)/Makefile \
 			$(CURDIR)/cargo-stage0
+
+build-cross:
+	DEB_BUILD_OPTIONS=nocheck sbuild --profiles=nocheck \
+	  --build-failed-commands '%SBUILD_SHELL' \
+	  --add-depends=libc-dev:$(DEB_HOST_ARCH) \
+	  $(EXTRA_SBUILD_FLAGS) \
+	  --host=$(DEB_HOST_ARCH) \
+	  --no-arch-all .
-- 
2.30.2