Makefile: don't compile all targets into target binaries

Currently target binaries contain support for all OS/arch combinations.
However, obviously a fuchsia target binary won't test windows.
For target binaries we need support only for a single target
(with the exception of 386/arm target in amd64/arm64 binaries).
So compile in only _the_ target into target binaries.
This reduces akaros/amd64 fuzzer binary from 33 to 7 MB
and execprog from 28 to 2 MB.

4 files changed, 16 insertions, 11 deletions

diff --git a/sys/fuchsia/gen/amd64.go b/sys/fuchsia/gen/amd64.go
index 63d7a8ff2..8e91dd584 100644
--- a/sys/fuchsia/gen/amd64.go
+++ b/sys/fuchsia/gen/amd64.go
@@ -1,10 +1,14 @@
 // AUTOGENERATED FILE
+// +build !syz_target syz_target,syz_os_fuchsia,syz_arch_amd64
 
 package gen
 
 import . "github.com/google/syzkaller/prog"
+import . "github.com/google/syzkaller/sys/fuchsia"
 
-var Target_amd64 = &Target{OS: "fuchsia", Arch: "amd64", Revision: revision_amd64, PtrSize: 8, PageSize: 4096, NumPages: 4096, DataOffset: 536870912, Syscalls: syscalls_amd64, Resources: resources_amd64, Structs: structDescs_amd64, Consts: consts_amd64}
+func init() {
+	RegisterTarget(&Target{OS: "fuchsia", Arch: "amd64", Revision: revision_amd64, PtrSize: 8, PageSize: 4096, NumPages: 4096, DataOffset: 536870912, Syscalls: syscalls_amd64, Resources: resources_amd64, Structs: structDescs_amd64, Consts: consts_amd64}, InitTarget)
+}
 
 var resources_amd64 = []*ResourceDesc{
 	{Name: "fd", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"fd"}, Values: []uint64{18446744073709551615, 18446744073709551516}},
@@ -1317,4 +1321,4 @@ var consts_amd64 = []ConstValue{
 	{Name: "ZX_WAIT_ASYNC_REPEATING", Value: 1},
 }
 
-const revision_amd64 = "9540132f74bbe9bfb7e8f215844bdb3a88b9a665"
+const revision_amd64 = "4cc56cb437136b65655dd3e0d9389be66131c7d1"
diff --git a/sys/fuchsia/gen/arm64.go b/sys/fuchsia/gen/arm64.go
index 326d53079..69bc14651 100644
--- a/sys/fuchsia/gen/arm64.go
+++ b/sys/fuchsia/gen/arm64.go
@@ -1,10 +1,14 @@
 // AUTOGENERATED FILE
+// +build !syz_target syz_target,syz_os_fuchsia,syz_arch_arm64
 
 package gen
 
 import . "github.com/google/syzkaller/prog"
+import . "github.com/google/syzkaller/sys/fuchsia"
 
-var Target_arm64 = &Target{OS: "fuchsia", Arch: "arm64", Revision: revision_arm64, PtrSize: 8, PageSize: 4096, NumPages: 4096, DataOffset: 536870912, Syscalls: syscalls_arm64, Resources: resources_arm64, Structs: structDescs_arm64, Consts: consts_arm64}
+func init() {
+	RegisterTarget(&Target{OS: "fuchsia", Arch: "arm64", Revision: revision_arm64, PtrSize: 8, PageSize: 4096, NumPages: 4096, DataOffset: 536870912, Syscalls: syscalls_arm64, Resources: resources_arm64, Structs: structDescs_arm64, Consts: consts_arm64}, InitTarget)
+}
 
 var resources_arm64 = []*ResourceDesc{
 	{Name: "fd", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"fd"}, Values: []uint64{18446744073709551615, 18446744073709551516}},
@@ -1317,4 +1321,4 @@ var consts_arm64 = []ConstValue{
 	{Name: "ZX_WAIT_ASYNC_REPEATING", Value: 1},
 }
 
-const revision_arm64 = "ebb425942f2bbfd2db293e4a2a0a417f6aaafb1c"
+const revision_arm64 = "42ba25aa193b27b48c8f8ade1c9186cb89c7ca61"
diff --git a/sys/fuchsia/gen/empty.go b/sys/fuchsia/gen/empty.go
new file mode 100644
index 000000000..5baff07bf
--- /dev/null
+++ b/sys/fuchsia/gen/empty.go
@@ -0,0 +1,3 @@
+// AUTOGENERATED FILE
+// This file is needed if OS is completely excluded by build tags.
+package gen
diff --git a/sys/fuchsia/init.go b/sys/fuchsia/init.go
index 3f02e151d..eefba3950 100644
--- a/sys/fuchsia/init.go
+++ b/sys/fuchsia/init.go
@@ -5,15 +5,9 @@ package fuchsia
 
 import (
 	"github.com/google/syzkaller/prog"
-	"github.com/google/syzkaller/sys/fuchsia/gen"
 	"github.com/google/syzkaller/sys/targets"
 )
 
-func init() {
-	prog.RegisterTarget(gen.Target_amd64, initTarget)
-	prog.RegisterTarget(gen.Target_arm64, initTarget)
-}
-
-func initTarget(target *prog.Target) {
+func InitTarget(target *prog.Target) {
 	target.MakeMmap = targets.MakeSyzMmap(target)
 }