[Buildroot] [PATCHv6] package/golang: new package

[Buildroot] [PATCHv6] package/golang: new package

[Yann E. MORIN]

From: Christian Stewart <christian@paral.in>

This patch adds golang, the Go compiler-and-interpreter.

We're adding a host package to get the golang cross-compiler, and a
target package to get the golang interpreter on the target.

It is to be noted that golang's buildsystem is going at great length to
not do anything like any other buildsystem, and is full of little
tricks.

First-off, even though it generates code for the target, the host-variant
does not need the toolchain; it has its own built-in code generator. Yet,
building the target variant, the toolchain is indeed required. Weird...

Second, it misdetects cross-compilation: it considers that if the target
CPU and the build CPU are the same, then this is not cross-compilation.
Of course, this is completely stupid and wrong. So, we need to patch it
to override its insane heuristic.

Third, even so, when the target CPU is the same as the build CPU, the
resulting binaries will be dynamically linked, otherwise, they are
statically linked. We can't even force it one way or the other...
Instead, we mark it as requiring dynamic libraries, and let the golang
ill buildsystem decide whether to do static or dynamic link; we can do
so because any sane toolchain will always have the static variants of
the libc and libpthread, which is all that golang requires anyway.

Signed-off-by: Christian Stewart <christian@paral.in>
[yann.morin.1998 at free.fr:
 - add architecture-specific options
 - needs dynamic linking
 - fix licensing info
 - fix tab-space indentation in patch 0003
 - fix offset in patch 0001
 - misc cleanups
]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

---
Changes v4 -> v6;
  - origin of hash  (Thomas)
  - better indent commands  (Thomas)
  - don't "deinstall" prior to installing  (Thomas)
  - fix offset in patch 0001

Changes v3 -> v4;
  - adopted by Yann, worked on in concert with Christian
  - lots of refactoring and cleanups
---
 package/Config.in                                  |  1 +
 package/golang/0001-add-no-march-option-gccp.patch | 21 ++++++
 .../0002-remove-unnecessary-march-ld-flag.patch    | 29 ++++++++
 package/golang/0003-fix-make-bash-script.patch     | 41 +++++++++++
 package/golang/Config.in                           | 22 ++++++
 package/golang/golang.hash                         |  2 +
 package/golang/golang.mk                           | 84 ++++++++++++++++++++++
 7 files changed, 200 insertions(+)
 create mode 100644 package/golang/0001-add-no-march-option-gccp.patch
 create mode 100644 package/golang/0002-remove-unnecessary-march-ld-flag.patch
 create mode 100644 package/golang/0003-fix-make-bash-script.patch
 create mode 100644 package/golang/Config.in
 create mode 100644 package/golang/golang.hash
 create mode 100644 package/golang/golang.mk

diff --git a/package/Config.in b/package/Config.in
index 2528238..3e18221 100644
--- a/package/Config.in
+++ b/package/Config.in
@@ -460,6 +460,7 @@ menu "Erlang libraries/modules"
 	source "package/erlang-p1-zlib/Config.in"
 endmenu
 endif
+	source "package/golang/Config.in"
 	source "package/guile/Config.in"
 	source "package/haserl/Config.in"
 	source "package/jamvm/Config.in"
diff --git a/package/golang/0001-add-no-march-option-gccp.patch b/package/golang/0001-add-no-march-option-gccp.patch
new file mode 100644
index 0000000..4139c57
--- /dev/null
+++ b/package/golang/0001-add-no-march-option-gccp.patch
@@ -0,0 +1,21 @@
+Adds an option to not add the problematic -m parameter to GCC.
+
+Signed-off-by: Christian Stewart <christian@paral.in>
+[yann.morin.1998 at free.fr: fix offset]
+Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
+
+diff -Nau golang.orig/src/cmd/cgo/gcc.go golang/src/cmd/cgo/gcc.go
+--- golang.orig/src/cmd/cgo/gcc.go.orig	2015-07-09 15:53:55.720794139 -0700
++++ golang/src/cmd/cgo/gcc.go	2015-07-09 17:46:43.664496374 -0700
+@@ -739,6 +739,11 @@
+ 
+ // gccMachine returns the gcc -m flag to use, either "-m32", "-m64" or "-marm".
+ func (p *Package) gccMachine() []string {
++
++	if os.Getenv("CGO_NO_EMULATION") == "1" {
++		return nil
++	}
++
+ 	switch goarch {
+ 	case "amd64":
+ 		return []string{"-m64"}
diff --git a/package/golang/0002-remove-unnecessary-march-ld-flag.patch b/package/golang/0002-remove-unnecessary-march-ld-flag.patch
new file mode 100644
index 0000000..7cc20f4
--- /dev/null
+++ b/package/golang/0002-remove-unnecessary-march-ld-flag.patch
@@ -0,0 +1,29 @@
+Removes defining -m parameter to LD, which is unnecessary in buildroot.
+
+Signed-off-by: Christian Stewart <christian@paral.in>
+
+diff -Nau golang.orig/src/cmd/ld/lib.c golang/src/cmd/ld/lib.c
+--- golang.orig/src/cmd/ld/lib.c.orig	2015-07-09 18:38:44.192359082 -0700
++++ golang/src/cmd/ld/lib.c	2015-07-09 18:39:02.108358294 -0700
+@@ -589,20 +589,7 @@
+ 	if(extld == nil)
+ 		extld = "gcc";
+ 	argv[argc++] = extld;
+-	switch(thechar){
+-	case '8':
+-		argv[argc++] = "-m32";
+-		break;
+-	case '6':
+-		argv[argc++] = "-m64";
+-		break;
+-	case '5':
+-		argv[argc++] = "-marm";
+-		break;
+-	}
+-	if(!debug['s'] && !debug_s) {
+-		argv[argc++] = "-gdwarf-2"; 
+-	} else {
++	if(debug['s'] || debug_s) {
+ 		argv[argc++] = "-s";
+ 	}
+ 	if(HEADTYPE == Hdarwin)
diff --git a/package/golang/0003-fix-make-bash-script.patch b/package/golang/0003-fix-make-bash-script.patch
new file mode 100644
index 0000000..6a35457
--- /dev/null
+++ b/package/golang/0003-fix-make-bash-script.patch
@@ -0,0 +1,41 @@
+make.bash: fix cross-compile when target is same arch as host
+
+Add options GO_NO_HOST and GO_NO_TARGET to make.bash and copy binaries
+into specific directories depending on the target.
+
+Signed-off-by: Christian Stewart <christian@paral.in>
+[yann.morin.1998 at free.fr: fix tab-space indentation issues]
+Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
+
+diff -durN golang-1.4.2.orig/src/make.bash golang-1.4.2/src/make.bash
+--- golang-1.4.2.orig/src/make.bash	2015-02-18 05:38:34.000000000 +0100
++++ golang-1.4.2/src/make.bash	2015-07-28 23:00:26.375589973 +0200
+@@ -161,18 +161,24 @@
+ "$GOTOOLDIR"/go_bootstrap clean -i std
+ echo
+ 
+-if [ "$GOHOSTARCH" != "$GOARCH" -o "$GOHOSTOS" != "$GOOS" ]; then
++if [ -z "$GO_NO_HOST" ]; then
+ 	echo "# Building packages and commands for host, $GOHOSTOS/$GOHOSTARCH."
+ 	# CC_FOR_TARGET is recorded as the default compiler for the go tool. When building for the host, however,
+ 	# use the host compiler, CC, from `cmd/dist/dist env` instead.
+ 	CC=$CC GOOS=$GOHOSTOS GOARCH=$GOHOSTARCH \
+ 		"$GOTOOLDIR"/go_bootstrap install -ccflags "$GO_CCFLAGS" -gcflags "$GO_GCFLAGS" -ldflags "$GO_LDFLAGS" -v std
+ 	echo
++	mkdir -p ../bin/host/
++	find ../bin/ -maxdepth 1 -type f -exec mv -i {} ../bin/host/ \;
+ fi
+ 
+-echo "# Building packages and commands for $GOOS/$GOARCH."
+-CC=$CC_FOR_TARGET "$GOTOOLDIR"/go_bootstrap install $GO_FLAGS -ccflags "$GO_CCFLAGS" -gcflags "$GO_GCFLAGS" -ldflags "$GO_LDFLAGS" -v std
+-echo
++if [ -z "$GO_NO_TARGET" ]; then
++	echo "# Building packages and commands for $GOOS/$GOARCH."
++	CC=$CC_FOR_TARGET "$GOTOOLDIR"/go_bootstrap install $GO_FLAGS -ccflags "$GO_CCFLAGS" -gcflags "$GO_GCFLAGS" -ldflags "$GO_LDFLAGS" -v std
++	echo
++	mkdir -p ../bin/${GOOS}_${GOARCH}/
++	find ../bin/ -maxdepth 1 -type f -exec mv -i {} ../bin/${GOOS}_${GOARCH}/ \;
++fi
+ 
+ rm -f "$GOTOOLDIR"/go_bootstrap
+ 
diff --git a/package/golang/Config.in b/package/golang/Config.in
new file mode 100644
index 0000000..8dbd75a
--- /dev/null
+++ b/package/golang/Config.in
@@ -0,0 +1,22 @@
+comment "golang needs a toolchain w/ threads, dynamic library"
+	depends on BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
+	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS
+
+# golang only supports x86, x86_64 and ARM (LE) targets.
+# For ARM, armv5 or above is required.
+config BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
+	bool
+	default y
+	depends on BR2_USE_MMU
+	depends on BR2_i386 || BR2_x86_64 || BR2_arm
+	depends on !BR2_ARM_CPU_ARMV4
+
+config BR2_PACKAGE_GOLANG
+	bool "golang"
+	depends on BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
+	depends on !BR2_STATIC_LIBS
+	depends on BR2_TOOLCHAIN_HAS_THREADS
+	help
+	  Go compiler and cli tool.
+
+	  http://golang.org/
diff --git a/package/golang/golang.hash b/package/golang/golang.hash
new file mode 100644
index 0000000..329cc54
--- /dev/null
+++ b/package/golang/golang.hash
@@ -0,0 +1,2 @@
+# Hash from: https://golang.org/dl/
+sha1 460caac03379f746c473814a65223397e9c9a2f6  go1.4.2.src.tar.gz
diff --git a/package/golang/golang.mk b/package/golang/golang.mk
new file mode 100644
index 0000000..58d5847
--- /dev/null
+++ b/package/golang/golang.mk
@@ -0,0 +1,84 @@
+################################################################################
+#
+# GOLANG
+#
+################################################################################
+
+GOLANG_VERSION = 1.4.2
+GOLANG_SOURCE = go$(GOLANG_VERSION).src.tar.gz
+GOLANG_SITE = https://storage.googleapis.com/golang
+GOLANG_LICENSE = BSD-3c
+GOLANG_LICENSE_FILES = LICENSE
+
+GOLANG = $(HOST_DIR)/usr/bin/go
+GOLANGFMT = $(HOST_DIR)/usr/bin/gofmt
+
+GOLANG_ENV = \
+	CC_FOR_TARGET="$(TARGET_CC)" \
+	LD_FOR_TARGET="$(TARGET_LD)" \
+	GOOS=linux
+
+ifeq ($(BR2_i386),y)
+GOLANG_ARCH = 386
+ifeq ($(BR2_X86_CPU_HAS_SSE2),y)
+GOLANG_ENV += GO386=sse2
+else
+GOLANG_ENV += GO386=387
+endif
+endif # i386
+
+ifeq ($(BR2_x86_64),y)
+GOLANG_ARCH = amd64
+endif # x86_64
+
+# For ARM, the selection of the instruciton set is a bit unusual,
+# and is decided on whether the CPU has an FPU, and which one.
+ifeq ($(BR2_arm),y)
+GOLANG_ARCH = arm
+ifeq ($(BR2_ARM_CPU_HAS_VFPV3),y)
+GOLANG_ENV += GOARM=7
+else ifeq ($(BR2_ARM_CPU_HAS_VFPV2),y)
+GOLANG_ENV += GOARM=6
+else
+GOLANG_ENV += GOARM=5
+endif
+endif # arm
+
+GOLANG_ENV += GOARCH=$(GOLANG_ARCH)
+
+define GOLANG_BUILD_CMDS
+	cd $(@D)/src/; \
+		$(GOLANG_ENV) GOROOT_FINAL="/usr/lib/go" GO_NO_HOST=1 \
+			./make.bash --no-banner
+endef
+
+# We must install both the src/ and include/ subdirs because they
+# contain the go "runtime".
+define GOLANG_INSTALL_TARGET_CMDS
+	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/go $(TARGET_DIR)/usr/bin/go
+	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/gofmt $(TARGET_DIR)/usr/bin/gofmt
+	mkdir -p $(TARGET_DIR)/usr/lib/go/
+	cp -a $(@D)/src $(TARGET_DIR)/usr/lib/go/
+	cp -a $(@D)/include $(TARGET_DIR)/usr/lib/go/
+	cp -a $(@D)/pkg $(TARGET_DIR)/usr/lib/go/
+endef
+
+define HOST_GOLANG_BUILD_CMDS
+	cd $(@D)/src/ ; \
+		$(GOLANG_ENV) GOROOT_FINAL="$(HOST_DIR)/usr/lib/go" GO_NO_TARGET=1 \
+			./make.bash --no-banner
+endef
+
+# We must install both the src/ and include/ subdirs because they
+# contain the go "runtime"
+define HOST_GOLANG_INSTALL_CMDS
+	$(INSTALL) -D -m 0755 $(@D)/bin/host/go $(HOST_DIR)/usr/bin/go
+	$(INSTALL) -D -m 0755 $(@D)/bin/host/gofmt $(HOST_DIR)/usr/bin/gofmt
+	mkdir -p $(HOST_DIR)/usr/lib/go/
+	cp -a $(@D)/src $(HOST_DIR)/usr/lib/go/
+	cp -a $(@D)/include $(HOST_DIR)/usr/lib/go/
+	cp -a $(@D)/pkg $(HOST_DIR)/usr/lib/go/
+endef
+
+$(eval $(generic-package))
+$(eval $(host-generic-package))
-- 
1.9.1

[Buildroot] [PATCHv6] package/golang: new package

[Jerzy Grzegorek]

Hi Yann,

> From: Christian Stewart <christian@paral.in>
>
> This patch adds golang, the Go compiler-and-interpreter.
>
> We're adding a host package to get the golang cross-compiler, and a
> target package to get the golang interpreter on the target.
>
> It is to be noted that golang's buildsystem is going at great length to
> not do anything like any other buildsystem, and is full of little
> tricks.
>
> First-off, even though it generates code for the target, the host-variant
> does not need the toolchain; it has its own built-in code generator. Yet,
> building the target variant, the toolchain is indeed required. Weird...
>
> Second, it misdetects cross-compilation: it considers that if the target
> CPU and the build CPU are the same, then this is not cross-compilation.
> Of course, this is completely stupid and wrong. So, we need to patch it
> to override its insane heuristic.
>
> Third, even so, when the target CPU is the same as the build CPU, the
> resulting binaries will be dynamically linked, otherwise, they are
> statically linked. We can't even force it one way or the other...
> Instead, we mark it as requiring dynamic libraries, and let the golang
> ill buildsystem decide whether to do static or dynamic link; we can do
> so because any sane toolchain will always have the static variants of
> the libc and libpthread, which is all that golang requires anyway.
>
> Signed-off-by: Christian Stewart <christian@paral.in>
> [yann.morin.1998 at free.fr:
>   - add architecture-specific options
>   - needs dynamic linking
>   - fix licensing info
>   - fix tab-space indentation in patch 0003
>   - fix offset in patch 0001
>   - misc cleanups
> ]
> Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
>
> ---
> Changes v4 -> v6;
>    - origin of hash  (Thomas)
>    - better indent commands  (Thomas)
>    - don't "deinstall" prior to installing  (Thomas)
>    - fix offset in patch 0001
>
> Changes v3 -> v4;
>    - adopted by Yann, worked on in concert with Christian
>    - lots of refactoring and cleanups
> ---
>   package/Config.in                                  |  1 +
>   package/golang/0001-add-no-march-option-gccp.patch | 21 ++++++
>   .../0002-remove-unnecessary-march-ld-flag.patch    | 29 ++++++++
>   package/golang/0003-fix-make-bash-script.patch     | 41 +++++++++++
>   package/golang/Config.in                           | 22 ++++++
>   package/golang/golang.hash                         |  2 +
>   package/golang/golang.mk                           | 84 ++++++++++++++++++++++
>   7 files changed, 200 insertions(+)
>   create mode 100644 package/golang/0001-add-no-march-option-gccp.patch
>   create mode 100644 package/golang/0002-remove-unnecessary-march-ld-flag.patch
>   create mode 100644 package/golang/0003-fix-make-bash-script.patch
>   create mode 100644 package/golang/Config.in
>   create mode 100644 package/golang/golang.hash
>   create mode 100644 package/golang/golang.mk
>

[...]

> diff --git a/package/golang/golang.mk b/package/golang/golang.mk
> new file mode 100644
> index 0000000..58d5847
> --- /dev/null
> +++ b/package/golang/golang.mk
> @@ -0,0 +1,84 @@
> +################################################################################
> +#
> +# GOLANG

This should be in lowercase.

Regards,
Jerzy

> +#
> +################################################################################
> +
> +GOLANG_VERSION = 1.4.2
> +GOLANG_SOURCE = go$(GOLANG_VERSION).src.tar.gz
> +GOLANG_SITE = https://storage.googleapis.com/golang
> +GOLANG_LICENSE = BSD-3c
> +GOLANG_LICENSE_FILES = LICENSE
> +
> +GOLANG = $(HOST_DIR)/usr/bin/go
> +GOLANGFMT = $(HOST_DIR)/usr/bin/gofmt
> +
> +GOLANG_ENV = \
> +	CC_FOR_TARGET="$(TARGET_CC)" \
> +	LD_FOR_TARGET="$(TARGET_LD)" \
> +	GOOS=linux
> +
> +ifeq ($(BR2_i386),y)
> +GOLANG_ARCH = 386
> +ifeq ($(BR2_X86_CPU_HAS_SSE2),y)
> +GOLANG_ENV += GO386=sse2
> +else
> +GOLANG_ENV += GO386=387
> +endif
> +endif # i386
> +
> +ifeq ($(BR2_x86_64),y)
> +GOLANG_ARCH = amd64
> +endif # x86_64
> +
> +# For ARM, the selection of the instruciton set is a bit unusual,
> +# and is decided on whether the CPU has an FPU, and which one.
> +ifeq ($(BR2_arm),y)
> +GOLANG_ARCH = arm
> +ifeq ($(BR2_ARM_CPU_HAS_VFPV3),y)
> +GOLANG_ENV += GOARM=7
> +else ifeq ($(BR2_ARM_CPU_HAS_VFPV2),y)
> +GOLANG_ENV += GOARM=6
> +else
> +GOLANG_ENV += GOARM=5
> +endif
> +endif # arm
> +
> +GOLANG_ENV += GOARCH=$(GOLANG_ARCH)
> +
> +define GOLANG_BUILD_CMDS
> +	cd $(@D)/src/; \
> +		$(GOLANG_ENV) GOROOT_FINAL="/usr/lib/go" GO_NO_HOST=1 \
> +			./make.bash --no-banner
> +endef
> +
> +# We must install both the src/ and include/ subdirs because they
> +# contain the go "runtime".
> +define GOLANG_INSTALL_TARGET_CMDS
> +	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/go $(TARGET_DIR)/usr/bin/go
> +	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/gofmt $(TARGET_DIR)/usr/bin/gofmt
> +	mkdir -p $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/src $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/include $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/pkg $(TARGET_DIR)/usr/lib/go/
> +endef
> +
> +define HOST_GOLANG_BUILD_CMDS
> +	cd $(@D)/src/ ; \
> +		$(GOLANG_ENV) GOROOT_FINAL="$(HOST_DIR)/usr/lib/go" GO_NO_TARGET=1 \
> +			./make.bash --no-banner
> +endef
> +
> +# We must install both the src/ and include/ subdirs because they
> +# contain the go "runtime"
> +define HOST_GOLANG_INSTALL_CMDS
> +	$(INSTALL) -D -m 0755 $(@D)/bin/host/go $(HOST_DIR)/usr/bin/go
> +	$(INSTALL) -D -m 0755 $(@D)/bin/host/gofmt $(HOST_DIR)/usr/bin/gofmt
> +	mkdir -p $(HOST_DIR)/usr/lib/go/
> +	cp -a $(@D)/src $(HOST_DIR)/usr/lib/go/
> +	cp -a $(@D)/include $(HOST_DIR)/usr/lib/go/
> +	cp -a $(@D)/pkg $(HOST_DIR)/usr/lib/go/
> +endef
> +
> +$(eval $(generic-package))
> +$(eval $(host-generic-package))

[Buildroot] [PATCHv6] package/golang: new package

[Thomas Petazzoni]

Yann, Christian,

On Thu, 30 Jul 2015 19:24:13 +0200, Yann E. MORIN wrote:

> We're adding a host package to get the golang cross-compiler, and a
> target package to get the golang interpreter on the target.

As discussed on IRC, I tested the host package, and it is not a
cross-compiler, but a regular compiler, which makes it pretty useless:

$ ./output/host/usr/bin/go build toto.go 
$ file toto
toto: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, not stripped

> diff --git a/package/golang/Config.in b/package/golang/Config.in
> new file mode 100644
> index 0000000..8dbd75a
> --- /dev/null
> +++ b/package/golang/Config.in
> @@ -0,0 +1,22 @@
> +comment "golang needs a toolchain w/ threads, dynamic library"
> +	depends on BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
> +	depends on !BR2_TOOLCHAIN_HAS_THREADS || BR2_STATIC_LIBS
> +
> +# golang only supports x86, x86_64 and ARM (LE) targets.
> +# For ARM, armv5 or above is required.
> +config BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
> +	bool
> +	default y
> +	depends on BR2_USE_MMU
> +	depends on BR2_i386 || BR2_x86_64 || BR2_arm
> +	depends on !BR2_ARM_CPU_ARMV4
> +
> +config BR2_PACKAGE_GOLANG
> +	bool "golang"
> +	depends on BR2_PACKAGE_GOLANG_ARCH_SUPPORTS
> +	depends on !BR2_STATIC_LIBS
> +	depends on BR2_TOOLCHAIN_HAS_THREADS
> +	help
> +	  Go compiler and cli tool.

I think this is fairly confusing. We should instead say:

	  Go interpreter.

and indicate that if people want to run Go applications that have been
built on their host machine, then they don't need the golang target
package.


> diff --git a/package/golang/golang.mk b/package/golang/golang.mk
> new file mode 100644
> index 0000000..58d5847
> --- /dev/null
> +++ b/package/golang/golang.mk
> @@ -0,0 +1,84 @@
> +################################################################################
> +#
> +# GOLANG

should be lower case, as already noted by Jerzy.


> +# We must install both the src/ and include/ subdirs because they
> +# contain the go "runtime".
> +define GOLANG_INSTALL_TARGET_CMDS
> +	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/go $(TARGET_DIR)/usr/bin/go
> +	$(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/gofmt $(TARGET_DIR)/usr/bin/gofmt

Why do we install gofmt on the target? Buildroot doesn't install tools
to do development on the target, so installing gofmt seems weird.

> +	mkdir -p $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/src $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/include $(TARGET_DIR)/usr/lib/go/
> +	cp -a $(@D)/pkg $(TARGET_DIR)/usr/lib/go/

If I understand correctly, all of this "runtime" is actually only
needed if you use "go" as an interpreter on the target. If you use "go"
on the host as a cross-compiler to build your application, you don't
need any of this "runtime". This stuff is actually quite huge (around
70 MB!).

Note that we more commonly use "cp -dprf" in Buildroot rather than "cp
-a", but I guess it's not a super-strict rule.

I've marked the patch as Changes Requested in patchwork.

Thanks!

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[Buildroot] [PATCHv6] package/golang: new package

[Christian Stewart]

Thomas,

... to everyone this time...


> Maybe the host-golang compiler needs to be passed some magic arguments
> or environment variables to build?
>

Yes, this is the case. You have to specify GOARCH and similar. It's done in
the docker package pull request, see

https://github.com/paralin/buildroot/blob/44464ffc4e67c3ee7483ac7b70c6bf67bda2e399/package/lxcdocker/lxcdocker.mk

These things are already not copied if only host-golang is built.
>

Then I don't see the issue. If you're wanting to use Go as an interpreter,
Go needs to be able to access all of the source code required to compile
the code and the dependencies. So, the runtime is required to be copied.

Thanks!
Christian
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[Buildroot] Fwd: [PATCHv6] package/golang: new package

[Christian Stewart]

---------- Forwarded message ---------
From: Christian Stewart <christian@paral.in>
Date: Wed, Oct 21, 2015 at 5:16 PM
Subject: Re: [Buildroot] [PATCHv6] package/golang: new package
To: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>


Thomas,

On Wed, Oct 21, 2015 at 5:11 PM Thomas Petazzoni <
thomas.petazzoni@free-electrons.com> wrote:

> As discussed on IRC, I tested the host package, and it is not a
> cross-compiler, but a regular compiler, which makes it pretty useless:
>

Odd. Yann, can you look into this? I think it works to cross-compile Docker.

I think this is fairly confusing. We should instead say:
>
>           Go interpreter.
>
> and indicate that if people want to run Go applications that have been
> built on their host machine, then they don't need the golang target
> package.
>

Sounds Ok to me.


> should be lower case, as already noted by Jerzy.
>

OK.


> > +# We must install both the src/ and include/ subdirs because they
> > +# contain the go "runtime".
> > +define GOLANG_INSTALL_TARGET_CMDS
> > +     $(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/go
> $(TARGET_DIR)/usr/bin/go
> > +     $(INSTALL) -D -m 0755 $(@D)/bin/linux_$(GOLANG_ARCH)/gofmt
> $(TARGET_DIR)/usr/bin/gofmt
>
> Why do we install gofmt on the target? Buildroot doesn't install tools
> to do development on the target, so installing gofmt seems weird.
>

I believe as an "interpreter" go uses gofmt a lot.


>
> > +     mkdir -p $(TARGET_DIR)/usr/lib/go/
> > +     cp -a $(@D)/src $(TARGET_DIR)/usr/lib/go/
> > +     cp -a $(@D)/include $(TARGET_DIR)/usr/lib/go/
> > +     cp -a $(@D)/pkg $(TARGET_DIR)/usr/lib/go/
>
> If I understand correctly, all of this "runtime" is actually only
> needed if you use "go" as an interpreter on the target. If you use "go"
> on the host as a cross-compiler to build your application, you don't
> need any of this "runtime". This stuff is actually quite huge (around
> 70 MB!).
>

Yes you don't need this as long as you've pre-compiled everything on the
target and don't want to use it as an interpreter. it shouldn't be copied
if the host is selected only.


> Note that we more commonly use "cp -dprf" in Buildroot rather than "cp
> -a", but I guess it's not a super-strict rule.


~ Christian
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[Buildroot] [PATCHv6] package/golang: new package

[Christian Stewart]

Thomas, Yann,

Is there anything that needs to be done regarding golang for it to be
merged? After golang we can push towards docker support.

Best,
Christian
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[Buildroot] [PATCHv6] package/golang: new package

[Yann E. MORIN]

Christian, All,

On 2015-11-04 15:39 +0000, Christian Stewart spake thusly:
> Is there anything that needs to be done regarding golang for it to be
> merged? After golang we can push towards docker support.

IIRC, we need to provide an $(TUPLE)-go to act as a cross-compiler. That
would be a shell script that exports the appropriate environement
variables (you provided the list) and then calls the real go executable.

Otherwise, just calling the go program, even when set up as a
cross-compiler, does not produce target binaries as we've observed.

Regards,
Yann E. MORIN.

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCHv6] package/golang: new package

[Thomas Petazzoni]

Hello,

On Wed, 4 Nov 2015 18:21:18 +0100, Yann E. MORIN wrote:

> On 2015-11-04 15:39 +0000, Christian Stewart spake thusly:
> > Is there anything that needs to be done regarding golang for it to be
> > merged? After golang we can push towards docker support.
> 
> IIRC, we need to provide an $(TUPLE)-go to act as a cross-compiler. That
> would be a shell script that exports the appropriate environement
> variables (you provided the list) and then calls the real go executable.
> 
> Otherwise, just calling the go program, even when set up as a
> cross-compiler, does not produce target binaries as we've observed.

Correct. Also, I think I raised a few comments (about gofmt, about the
situations where go in the target is useful). Those comments were
answered, but it would be nicer if the answers were turned into actual
comments into the code, or in the Config.in help text.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[Buildroot] [PATCHv6] package/golang: new package

[Christian Stewart]

Yann,

Would you like to address these or should I? If I add the command with env
variables variable as well as the docs, should I respin it or should I send
it to you? What's the best way to do this?

Correct. Also, I think I raised a few comments (about gofmt, about the
> situations where go in the target is useful). Those comments were
> answered, but it would be nicer if the answers were turned into actual
> comments into the code, or in the Config.in help text.
>

Thanks!
Christian
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[Buildroot] [PATCHv6] package/golang: new package

[Yann E. MORIN]

Christian, All,

On 2015-11-04 21:21 +0000, Christian Stewart spake thusly:
> Would you like to address these or should I? If I add the command with env
> variables variable as well as the docs, should I respin it or should I send
> it to you? What's the best way to do this?

Please do the change and respin a new patch to the list.

Thanks! :-)

Regards,
Yann E. MORIN.

> > Correct. Also, I think I raised a few comments (about gofmt, about the
> > situations where go in the target is useful). Those comments were
> > answered, but it would be nicer if the answers were turned into actual
> > comments into the code, or in the Config.in help text.
> >
> 
> Thanks!
> Christian

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'