all: use baremetal build tag

This simplifies adding more baremetal targets, like a GameBoy Advance,
or baremetal x86 for unikernels.

compiler/compiler.go

@@ -226,7 +226,7 @@ func (c *Compiler) Compile(mainPath string) []error {
 					return path
 				} else if path == "syscall" {
 					for _, tag := range c.BuildTags {
-						if tag == "avr" || tag == "cortexm" || tag == "darwin" || tag == "riscv" {
+						if tag == "baremetal" || tag == "darwin" {
 							return path
 						}
 					}

compiler/gc.go

@@ -18,7 +18,7 @@ func (c *Compiler) needsStackObjects() bool {
 		return false
 	}
 	for _, tag := range c.BuildTags {
-		if tag == "cortexm" || tag == "tinygo.riscv" {
+		if tag == "baremetal" {
 			return false
 		}
 	}

src/machine/i2c.go

@@ -1,4 +1,4 @@
-// +build !stm32f4disco,!hifive1b
+// +build avr nrf sam stm32,!stm32f4disco
 
 package machine
 

src/machine/machine_generic.go

@@ -1,4 +1,4 @@
-// +build !avr,!nrf,!sam,!sifive,!stm32
+// +build !baremetal
 
 package machine
 

src/machine/spi.go

@@ -1,4 +1,4 @@
-// +build !stm32f407,!avr,!hifive1b
+// +build nrf sam stm32,!stm32f407
 
 package machine
 

src/os/file_other.go

@@ -1,4 +1,4 @@
-// +build avr cortexm tinygo.riscv wasm
+// +build baremetal wasm
 
 package os
 

src/os/file_unix.go

@@ -1,4 +1,4 @@
-// +build darwin linux,!avr,!cortexm,!tinygo.riscv
+// +build darwin linux,!baremetal
 
 package os
 

src/runtime/arch_arm.go

@@ -1,4 +1,4 @@
-// +build arm,!avr,!cortexm,!tinygo.riscv
+// +build arm,!baremetal
 
 package runtime
 

src/runtime/baremetal.go

@@ -1,4 +1,4 @@
-// +build avr cortexm tinygo.riscv
+// +build baremetal
 
 package runtime
 

src/runtime/gc_globals_conservative.go

@@ -1,5 +1,5 @@
 // +build gc.conservative
-// +build cortexm tinygo.riscv
+// +build baremetal
 
 package runtime
 

src/runtime/gc_globals_precise.go

@@ -1,5 +1,5 @@
 // +build gc.conservative
-// +build !cortexm,!tinygo.riscv
+// +build !baremetal
 
 package runtime
 

src/runtime/gc_stack_portable.go

@@ -1,5 +1,5 @@
 // +build gc.conservative
-// +build !cortexm,!tinygo.riscv
+// +build !baremetal
 
 package runtime
 

src/runtime/gc_stack_raw.go

@@ -1,5 +1,5 @@
 // +build gc.conservative
-// +build cortexm tinygo.riscv
+// +build baremetal
 
 package runtime
 

src/runtime/runtime_unix.go

@@ -1,4 +1,4 @@
-// +build darwin linux,!avr,!cortexm,!tinygo.riscv
+// +build darwin linux,!baremetal
 
 package runtime
 

src/syscall/syscall_baremetal.go

@@ -1,4 +1,4 @@
-// +build avr cortexm
+// +build baremetal
 
 package syscall
 

src/syscall/tables_baremetal.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build avr cortexm
+// +build baremetal
 
 package syscall
 

targets/avr.json

@@ -1,5 +1,5 @@
 {
-	"build-tags": ["avr", "linux", "arm"],
+	"build-tags": ["avr", "baremetal", "linux", "arm"],
 	"goos": "linux",
 	"goarch": "arm",
 	"compiler": "avr-gcc",

targets/cortex-m.json

@@ -1,5 +1,5 @@
 {
-	"build-tags": ["cortexm", "linux", "arm"],
+	"build-tags": ["cortexm", "baremetal", "linux", "arm"],
 	"goos": "linux",
 	"goarch": "arm",
 	"compiler": "clang",

targets/riscv.json

@@ -2,7 +2,7 @@
 	"llvm-target": "riscv32--none",
 	"goos": "linux",
 	"goarch": "arm",
-	"build-tags": ["tinygo.riscv", "linux", "arm"],
+	"build-tags": ["tinygo.riscv", "baremetal", "linux", "arm"],
 	"gc": "conservative",
 	"compiler": "riscv64-unknown-elf-gcc",
 	"linker": "riscv64-unknown-elf-ld",