Add ESP32-C6 support

.github/workflows/build-macos.yml

@@ -40,7 +40,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Restore LLVM source cache
         uses: actions/cache/restore@v4
@@ -135,7 +135,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Build TinyGo (LLVM ${{ matrix.version }})
         run: go install -tags=llvm${{ matrix.version }}

.github/workflows/linux.yml

@@ -137,7 +137,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Install wasmtime
         uses: bytecodealliance/actions/wasmtime/setup@v1
@@ -181,7 +181,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Install Node.js
         uses: actions/setup-node@v4
@@ -298,7 +298,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Restore LLVM source cache
         uses: actions/cache/restore@v4

.github/workflows/nix.yml

@@ -42,7 +42,7 @@ jobs:
           key: ${{ steps.cache-llvm-source.outputs.cache-primary-key }}
           path: |
             llvm-project/compiler-rt
-      - uses: cachix/install-nix-action@v22
+      - uses: cachix/install-nix-action@v31
       - name: Test
         run: |
           nix develop --ignore-environment --keep HOME --command bash -c "go install && ~/go/bin/tinygo version && ~/go/bin/tinygo build -o test ./testdata/cgo"

.github/workflows/windows.yml

@@ -41,7 +41,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Restore cached LLVM source
         uses: actions/cache/restore@v4
@@ -147,7 +147,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Download TinyGo build
         uses: actions/download-artifact@v4
@@ -177,7 +177,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Download TinyGo build
         uses: actions/download-artifact@v4
@@ -213,7 +213,7 @@ jobs:
       - name: Install Go
         uses: actions/setup-go@v6
         with:
-          go-version: '1.25.5'
+          go-version: '1.25.7'
           cache: true
       - name: Download TinyGo build
         uses: actions/download-artifact@v4

GNUmakefile

@@ -814,6 +814,10 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=waveshare-rp2040-tiny examples/echo
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=vicharak_shrike-lite examples/echo
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=xiao-rp2350        examples/blinky1
+	@$(MD5SUM) test.hex
 	# test pwm
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-m0        examples/pwm
 	@$(MD5SUM) test.hex
@@ -896,13 +900,19 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=digispark           examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=digispark           examples/pwm
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=digispark           examples/mcp3008
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=digispark -gc=leaking examples/blinky1
 	@$(MD5SUM) test.hex
 ifneq ($(XTENSA), 0)
 	$(TINYGO) build -size short -o test.bin -target=esp32-mini32      	examples/blinky1
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini   examples/blinky1
 	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini   examples/blinkm
+	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=nodemcu             examples/blinky1
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target m5stack-core2       examples/machinetest
@@ -915,9 +925,40 @@ ifneq ($(XTENSA), 0)
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target mch2022             examples/machinetest
 	@$(MD5SUM) test.bin
+	# xiao-esp32s3
 	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/blinky1
 	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/blinkm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/mcp3008
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/pwm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/adc
+	@$(MD5SUM) test.bin
+
+	# esp32s3-wroom1
+	$(TINYGO) build -size short -o test.bin -target=esp32s3-wroom1	    examples/blinkm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32s3-wroom1	    examples/mcp3008
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32s3-wroom1   	examples/pwm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=xiao-esp32s3   		examples/adc
+	@$(MD5SUM) test.bin
 endif
+    # esp32c3-supermini
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini	    examples/blinky1
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini	    examples/blinkm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini	    examples/mcp3008
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini   	examples/pwm
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini   	examples/adc
+	@$(MD5SUM) test.bin
+
 	$(TINYGO) build -size short -o test.bin -target=esp-c3-32s-kit      examples/blinky1
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=qtpy-esp32c3        examples/machinetest
@@ -930,6 +971,9 @@ endif
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=esp32c3-12f         examples/blinky1
 	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c6	            examples/machinetest
+	@$(MD5SUM) test.bin
+
 	$(TINYGO) build -size short -o test.bin -target=makerfabs-esp32c3spi35 examples/machinetest
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.hex -target=hifive1b            examples/blinky1

README.md

@@ -6,6 +6,9 @@ TinyGo is a Go compiler intended for use in small places such as microcontroller
 
 It reuses libraries used by the [Go language tools](https://golang.org/pkg/go/) alongside [LLVM](http://llvm.org) to provide an alternative way to compile programs written in the Go programming language.
 
+> [!IMPORTANT]
+> You can help TinyGo with a financial contribution using OpenCollective. Please see https://opencollective.com/tinygo for more information. Thank you!
+
 ## Embedded
 
 Here is an example program that blinks the built-in LED when run directly on any supported board with onboard LED:
@@ -63,7 +66,7 @@ tinygo build -buildmode=c-shared -o add.wasm -target=wasip1 add.go
 You can also use the same syntax as Go 1.24+:
 
 ```shell
-GOARCH=wasip1 GOOS=wasm tinygo build -buildmode=c-shared -o add.wasm add.go
+GOOS=wasip1 GOARCH=wasm tinygo build -buildmode=c-shared -o add.wasm add.go
 ```
 
 ## Installation

builder/build.go

@@ -19,6 +19,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -281,9 +282,13 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 				allFiles[file.Name] = append(allFiles[file.Name], file)
 			}
 		}
-		for name, files := range allFiles {
-			name := name
-			files := files
+		// Sort embedded files by name to maintain output determinism.
+		embedNames := make([]string, 0, len(allFiles))
+		for _, files := range allFiles {
+			embedNames = append(embedNames, files[0].Name)
+		}
+		slices.Sort(embedNames)
+		for _, name := range embedNames {
 			job := &compileJob{
 				description: "make object file for " + name,
 				run: func(job *compileJob) error {
@@ -298,7 +303,7 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 					sum := sha256.Sum256(data)
 					hexSum := hex.EncodeToString(sum[:16])
 
-					for _, file := range files {
+					for _, file := range allFiles[name] {
 						file.Size = uint64(len(data))
 						file.Hash = hexSum
 						if file.NeedsData {
@@ -1042,7 +1047,7 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 		if err != nil {
 			return result, err
 		}
-	case "esp32", "esp32-img", "esp32c3", "esp32s3", "esp8266":
+	case "esp32", "esp32-img", "esp32c3", "esp32c6", "esp32s3", "esp8266":
 		// Special format for the ESP family of chips (parsed by the ROM
 		// bootloader).
 		result.Binary = filepath.Join(tmpdir, "main"+outext)

builder/builder_test.go

@@ -28,6 +28,7 @@ func TestClangAttributes(t *testing.T) {
 		"cortex-m4",
 		"cortex-m7",
 		"esp32c3",
+		"esp32c6",
 		"esp32s3",
 		"fe310",
 		"gameboy-advance",

builder/esp.go

@@ -9,7 +9,6 @@ package builder
 
 import (
 	"bytes"
-	"crypto/sha256"
 	"debug/elf"
 	"encoding/binary"
 	"fmt"
@@ -100,12 +99,24 @@ func makeESPFirmwareImage(infile, outfile, format string) error {
 	chip_id := map[string]uint16{
 		"esp32":   0x0000,
 		"esp32c3": 0x0005,
+		"esp32c6": 0x000D,
 		"esp32s3": 0x0009,
 	}[chip]
 
+	// SPI flash speed/size byte (byte 3 of header):
+	//   Upper nibble = flash size, lower nibble = flash frequency.
+	//   The espflasher auto-detects and patches the flash size (upper nibble),
+	//   but the frequency (lower nibble) must be correct per chip.
+	spiSpeedSize := map[string]uint8{
+		"esp32":   0x1f, // 80MHz=0x0F, 2MB=0x10
+		"esp32c3": 0x1f, // 80MHz=0x0F, 2MB=0x10
+		"esp32c6": 0x10, // 80MHz=0x00, 2MB=0x10 (C6 uses different freq encoding)
+		"esp32s3": 0x1f, // 80MHz=0x0F, 2MB=0x10
+	}[chip]
+
 	// Image header.
 	switch chip {
-	case "esp32", "esp32c3", "esp32s3":
+	case "esp32", "esp32c3", "esp32c6", "esp32s3":
 		// Header format:
 		// https://github.com/espressif/esp-idf/blob/v4.3/components/bootloader_support/include/esp_app_format.h#L71
 		// Note: not adding a SHA256 hash as the binary is modified by
@@ -126,12 +137,12 @@ func makeESPFirmwareImage(infile, outfile, format string) error {
 		}{
 			magic:          0xE9,
 			segment_count:  byte(len(segments)),
-			spi_mode:       2,    // ESP_IMAGE_SPI_MODE_DIO
-			spi_speed_size: 0x1f, // ESP_IMAGE_SPI_SPEED_80M, ESP_IMAGE_FLASH_SIZE_2MB
+			spi_mode:       2, // ESP_IMAGE_SPI_MODE_DIO
+			spi_speed_size: spiSpeedSize,
 			entry_addr:     uint32(inf.Entry),
 			wp_pin:         0xEE, // disable WP pin
 			chip_id:        chip_id,
-			hash_appended:  true, // add a SHA256 hash
+			hash_appended:  false, // disabled: espflasher patches header, invalidating the hash
 		})
 	case "esp8266":
 		// Header format:
@@ -173,11 +184,9 @@ func makeESPFirmwareImage(infile, outfile, format string) error {
 	outf.Write(make([]byte, 15-outf.Len()%16))
 	outf.WriteByte(checksum)
 
-	if chip != "esp8266" {
-		// SHA256 hash (to protect against image corruption, not for security).
-		hash := sha256.Sum256(outf.Bytes())
-		outf.Write(hash[:])
-	}
+	// Note: SHA256 hash intentionally omitted. espflasher patches the header
+	// (SPI mode/speed/size), which invalidates the hash. The ROM would report
+	// "SHA-256 comparison failed" and boot anyway, so it's just noise.
 
 	// QEMU (or more precisely, qemu-system-xtensa from Espressif) expects the
 	// image to be a certain size.

builder/sizes_test.go

@@ -44,7 +44,7 @@ func TestBinarySize(t *testing.T) {
 		// microcontrollers
 		{"hifive1b", "examples/echo", 3668, 280, 0, 2244},
 		{"microbit", "examples/serial", 2694, 342, 8, 2248},
-		{"wioterminal", "examples/pininterrupt", 6837, 1491, 120, 6888},
+		{"wioterminal", "examples/pininterrupt", 7074, 1510, 120, 7248},
 
 		// TODO: also check wasm. Right now this is difficult, because
 		// wasm binaries are run through wasm-opt and therefore the

compiler/gc.go

@@ -99,6 +99,9 @@ func typeHasPointers(t llvm.Type) bool {
 		}
 		return false
 	case llvm.ArrayTypeKind:
+		if t.ArrayLength() == 0 {
+			return false
+		}
 		if typeHasPointers(t.ElementType()) {
 			return true
 		}