Skip to content

Windows: add i386 (windows/386) support #4629

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Apr 22, 2025
Merged

Windows: add i386 (windows/386) support #4629

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
17400cc
windows: add windows/386 support
aykevl Nov 22, 2024
13d6eeb
windows: use MSVCRT.DLL instead of UCRT on i386
aykevl Apr 7, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion .github/workflows/build-macos.yml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -92,7 +92,7 @@ jobs:
- name: make gen-device
run: make -j3 gen-device
- name: Test TinyGo
run: make test GOTESTFLAGS="-short"
run: make test GOTESTFLAGS="-only-current-os"
- name: Build TinyGo release tarball
run: make release -j3
- name: Test stdlib packages
Expand Down
2 changes: 1 addition & 1 deletion .github/workflows/windows.yml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -105,7 +105,7 @@ jobs:
run: make -j3 gen-device
- name: Test TinyGo
shell: bash
run: make test GOTESTFLAGS="-short"
run: make test GOTESTFLAGS="-only-current-os"
- name: Build TinyGo release tarball
shell: bash
run: make build/release -j4
Expand Down
12 changes: 10 additions & 2 deletions GNUmakefile
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -940,8 +940,9 @@ build/release: tinygo gen-device $(if $(filter 1,$(USE_SYSTEM_BINARYEN)),,binary
@mkdir -p build/release/tinygo/lib/clang/include
@mkdir -p build/release/tinygo/lib/CMSIS/CMSIS
@mkdir -p build/release/tinygo/lib/macos-minimal-sdk
@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/crt
@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/math
@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/stdio
@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-headers/defaults
@mkdir -p build/release/tinygo/lib/musl/arch
@mkdir -p build/release/tinygo/lib/musl/crt
Expand Down Expand Up @@ -997,10 +998,17 @@ endif
@cp -rp lib/musl/src/time build/release/tinygo/lib/musl/src
@cp -rp lib/musl/src/unistd build/release/tinygo/lib/musl/src
@cp -rp lib/musl/src/process build/release/tinygo/lib/musl/src
@cp -rp lib/mingw-w64/mingw-w64-crt/crt/pseudo-reloc.c build/release/tinygo/lib/mingw-w64/mingw-w64-crt/crt
@cp -rp lib/mingw-w64/mingw-w64-crt/def-include build/release/tinygo/lib/mingw-w64/mingw-w64-crt
@cp -rp lib/mingw-w64/mingw-w64-crt/gdtoa build/release/tinygo/lib/mingw-w64/mingw-w64-crt
@cp -rp lib/mingw-w64/mingw-w64-crt/include build/release/tinygo/lib/mingw-w64/mingw-w64-crt
@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/api-ms-win-crt-* build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/advapi32.def.in build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/kernel32.def.in build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
@cp -rp lib/mingw-w64/mingw-w64-crt/stdio/ucrt_* build/release/tinygo/lib/mingw-w64/mingw-w64-crt/stdio
@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/msvcrt.def.in build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
@cp -rp lib/mingw-w64/mingw-w64-crt/math/x86 build/release/tinygo/lib/mingw-w64/mingw-w64-crt/math
@cp -rp lib/mingw-w64/mingw-w64-crt/misc build/release/tinygo/lib/mingw-w64/mingw-w64-crt
@cp -rp lib/mingw-w64/mingw-w64-crt/stdio build/release/tinygo/lib/mingw-w64/mingw-w64-crt
@cp -rp lib/mingw-w64/mingw-w64-headers/crt/ build/release/tinygo/lib/mingw-w64/mingw-w64-headers
@cp -rp lib/mingw-w64/mingw-w64-headers/defaults/include build/release/tinygo/lib/mingw-w64/mingw-w64-headers/defaults
@cp -rp lib/mingw-w64/mingw-w64-headers/include build/release/tinygo/lib/mingw-w64/mingw-w64-headers
Expand Down
1 change: 1 addition & 0 deletions builder/builder_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -67,6 +67,7 @@ func TestClangAttributes(t *testing.T) {
{GOOS: "linux", GOARCH: "mipsle", GOMIPS: "softfloat"},
{GOOS: "darwin", GOARCH: "amd64"},
{GOOS: "darwin", GOARCH: "arm64"},
{GOOS: "windows", GOARCH: "386"},
{GOOS: "windows", GOARCH: "amd64"},
{GOOS: "windows", GOARCH: "arm64"},
} {
Expand Down
10 changes: 10 additions & 0 deletions builder/builtins.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@ package builder
import (
"os"
"path/filepath"
"strings"

"github.com/tinygo-org/tinygo/compileopts"
"github.com/tinygo-org/tinygo/goenv"
Expand Down Expand Up @@ -201,6 +202,11 @@ var avrBuiltins = []string{
"avr/udivmodqi4.S",
}

// Builtins needed specifically for windows/386.
var windowsI386Builtins = []string{
"i386/chkstk.S", // also _alloca
}

// libCompilerRT is a library with symbols required by programs compiled with
// LLVM. These symbols are for operations that cannot be emitted with a single
// instruction or a short sequence of instructions for that target.
Expand Down Expand Up @@ -229,6 +235,10 @@ var libCompilerRT = Library{
builtins = append(builtins, avrBuiltins...)
case "x86_64", "aarch64", "riscv64": // any 64-bit arch
builtins = append(builtins, genericBuiltins128...)
case "i386":
if strings.Split(target, "-")[2] == "windows" {
builtins = append(builtins, windowsI386Builtins...)
}
}
return builtins, nil
},
Expand Down
118 changes: 86 additions & 32 deletions builder/mingw-w64.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -30,25 +30,62 @@ var libMinGW = Library{
sourceDir: func() string { return filepath.Join(goenv.Get("TINYGOROOT"), "lib/mingw-w64") },
cflags: func(target, headerPath string) []string {
mingwDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib/mingw-w64")
return []string{
flags := []string{
"-nostdlibinc",
"-isystem", mingwDir + "/mingw-w64-crt/include",
"-isystem", mingwDir + "/mingw-w64-headers/crt",
"-isystem", mingwDir + "/mingw-w64-headers/include",
"-I", mingwDir + "/mingw-w64-headers/defaults/include",
"-I" + headerPath,
}
if strings.Split(target, "-")[0] == "i386" {
flags = append(flags,
"-D__MSVCRT_VERSION__=0x700", // Microsoft Visual C++ .NET 2002
"-D_WIN32_WINNT=0x0501", // target Windows XP
"-D_CRTBLD",
"-Wno-pragma-pack",
)
}
return flags
},
librarySources: func(target string) ([]string, error) {
// These files are needed so that printf and the like are supported.
sources := []string{
"mingw-w64-crt/stdio/ucrt_fprintf.c",
"mingw-w64-crt/stdio/ucrt_fwprintf.c",
"mingw-w64-crt/stdio/ucrt_printf.c",
"mingw-w64-crt/stdio/ucrt_snprintf.c",
"mingw-w64-crt/stdio/ucrt_sprintf.c",
"mingw-w64-crt/stdio/ucrt_vfprintf.c",
"mingw-w64-crt/stdio/ucrt_vprintf.c",
"mingw-w64-crt/stdio/ucrt_vsnprintf.c",
"mingw-w64-crt/stdio/ucrt_vsprintf.c",
var sources []string
if strings.Split(target, "-")[0] == "i386" {
// Old 32-bit x86 systems use msvcrt.dll.
sources = []string{
"mingw-w64-crt/crt/pseudo-reloc.c",
"mingw-w64-crt/gdtoa/dmisc.c",
"mingw-w64-crt/gdtoa/gdtoa.c",
"mingw-w64-crt/gdtoa/gmisc.c",
"mingw-w64-crt/gdtoa/misc.c",
"mingw-w64-crt/math/x86/exp2.S",
"mingw-w64-crt/math/x86/trunc.S",
"mingw-w64-crt/misc/___mb_cur_max_func.c",
"mingw-w64-crt/misc/lc_locale_func.c",
"mingw-w64-crt/misc/mbrtowc.c",
"mingw-w64-crt/misc/strnlen.c",
"mingw-w64-crt/misc/wcrtomb.c",
"mingw-w64-crt/misc/wcsnlen.c",
"mingw-w64-crt/stdio/acrt_iob_func.c",
"mingw-w64-crt/stdio/mingw_lock.c",
"mingw-w64-crt/stdio/mingw_pformat.c",
"mingw-w64-crt/stdio/mingw_vfprintf.c",
"mingw-w64-crt/stdio/mingw_vsnprintf.c",
}
} else {
// Anything somewhat modern (amd64, arm64) uses UCRT.
sources = []string{
"mingw-w64-crt/stdio/ucrt_fprintf.c",
"mingw-w64-crt/stdio/ucrt_fwprintf.c",
"mingw-w64-crt/stdio/ucrt_printf.c",
"mingw-w64-crt/stdio/ucrt_snprintf.c",
"mingw-w64-crt/stdio/ucrt_sprintf.c",
"mingw-w64-crt/stdio/ucrt_vfprintf.c",
"mingw-w64-crt/stdio/ucrt_vprintf.c",
"mingw-w64-crt/stdio/ucrt_vsnprintf.c",
"mingw-w64-crt/stdio/ucrt_vsprintf.c",
}
}
return sources, nil
},
Expand All @@ -63,27 +100,41 @@ var libMinGW = Library{
func makeMinGWExtraLibs(tmpdir, goarch string) []*compileJob {
var jobs []*compileJob
root := goenv.Get("TINYGOROOT")
// Normally all the api-ms-win-crt-*.def files are all compiled to a single
// .lib file. But to simplify things, we're going to leave them as separate
// files.
for _, name := range []string{
"kernel32.def.in",
"api-ms-win-crt-conio-l1-1-0.def",
"api-ms-win-crt-convert-l1-1-0.def.in",
"api-ms-win-crt-environment-l1-1-0.def",
"api-ms-win-crt-filesystem-l1-1-0.def",
"api-ms-win-crt-heap-l1-1-0.def",
"api-ms-win-crt-locale-l1-1-0.def",
"api-ms-win-crt-math-l1-1-0.def.in",
"api-ms-win-crt-multibyte-l1-1-0.def",
"api-ms-win-crt-private-l1-1-0.def.in",
"api-ms-win-crt-process-l1-1-0.def",
"api-ms-win-crt-runtime-l1-1-0.def.in",
"api-ms-win-crt-stdio-l1-1-0.def",
"api-ms-win-crt-string-l1-1-0.def",
"api-ms-win-crt-time-l1-1-0.def",
"api-ms-win-crt-utility-l1-1-0.def",
} {
var libs []string
if goarch == "386" {
libs = []string{
// x86 uses msvcrt.dll instead of UCRT for compatibility with old
// Windows versions.
"advapi32.def.in",
"kernel32.def.in",
"msvcrt.def.in",
}
} else {
// Use the modernized UCRT on new systems.
// Normally all the api-ms-win-crt-*.def files are all compiled to a
// single .lib file. But to simplify things, we're going to leave them
// as separate files.
libs = []string{
"advapi32.def.in",
"kernel32.def.in",
"api-ms-win-crt-conio-l1-1-0.def",
"api-ms-win-crt-convert-l1-1-0.def.in",
"api-ms-win-crt-environment-l1-1-0.def",
"api-ms-win-crt-filesystem-l1-1-0.def",
"api-ms-win-crt-heap-l1-1-0.def",
"api-ms-win-crt-locale-l1-1-0.def",
"api-ms-win-crt-math-l1-1-0.def.in",
"api-ms-win-crt-multibyte-l1-1-0.def",
"api-ms-win-crt-private-l1-1-0.def.in",
"api-ms-win-crt-process-l1-1-0.def",
"api-ms-win-crt-runtime-l1-1-0.def.in",
"api-ms-win-crt-stdio-l1-1-0.def",
"api-ms-win-crt-string-l1-1-0.def",
"api-ms-win-crt-time-l1-1-0.def",
"api-ms-win-crt-utility-l1-1-0.def",
}
}
for _, name := range libs {
outpath := filepath.Join(tmpdir, filepath.Base(name)+".lib")
inpath := filepath.Join(root, "lib/mingw-w64/mingw-w64-crt/lib-common/"+name)
job := &compileJob{
Expand All @@ -93,6 +144,9 @@ func makeMinGWExtraLibs(tmpdir, goarch string) []*compileJob {
defpath := inpath
var archDef, emulation string
switch goarch {
case "386":
archDef = "-DDEF_I386"
emulation = "i386pe"
case "amd64":
archDef = "-DDEF_X64"
emulation = "i386pep"
Expand Down
16 changes: 13 additions & 3 deletions compileopts/config.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -398,15 +398,25 @@ func (c *Config) LibcCFlags() []string {
case "mingw-w64":
root := goenv.Get("TINYGOROOT")
path := c.LibraryPath("mingw-w64")
return []string{
cflags := []string{
"-nostdlibinc",
"-isystem", filepath.Join(path, "include"),
"-isystem", filepath.Join(root, "lib", "mingw-w64", "mingw-w64-headers", "crt"),
"-isystem", filepath.Join(root, "lib", "mingw-w64", "mingw-w64-headers", "include"),
"-isystem", filepath.Join(root, "lib", "mingw-w64", "mingw-w64-headers", "defaults", "include"),
"-D_UCRT",
"-D_WIN32_WINNT=0x0a00", // target Windows 10
}
if c.GOARCH() == "386" {
cflags = append(cflags,
"-D__MSVCRT_VERSION__=0x700", // Microsoft Visual C++ .NET 2002
"-D_WIN32_WINNT=0x0501", // target Windows XP
)
} else {
cflags = append(cflags,
"-D_UCRT",
"-D_WIN32_WINNT=0x0a00", // target Windows 10
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

What consequences we would have with 0x0601 targeting Windows 7 here on x64 architecture?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Honestly I don't know. It probably works just fine (and if it doesn't we can change that). Note that it didn't change: "-D_WIN32_WINNT=0x0a00" was already there, so this doesn't modify behavior for modern (amd64/arm64) systems.

)
}
return cflags
case "":
// No libc specified, nothing to add.
return nil
Expand Down
20 changes: 14 additions & 6 deletions compileopts/target.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -433,14 +433,22 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
spec.Scheduler = "tasks"
spec.Linker = "ld.lld"
spec.Libc = "mingw-w64"
// Note: using a medium code model, low image base and no ASLR
// because Go doesn't really need those features. ASLR patches
// around issues for unsafe languages like C/C++ that are not
// normally present in Go (without explicitly opting in).
// For more discussion:
// https://groups.google.com/g/Golang-nuts/c/Jd9tlNc6jUE/m/Zo-7zIP_m3MJ?pli=1
switch options.GOARCH {
case "386":
spec.LDFlags = append(spec.LDFlags,
"-m", "i386pe",
"--major-os-version", "4",
"--major-subsystem-version", "4",
)
// __udivdi3 is not present in ucrt it seems.
spec.RTLib = "compiler-rt"
case "amd64":
// Note: using a medium code model, low image base and no ASLR
// because Go doesn't really need those features. ASLR patches
// around issues for unsafe languages like C/C++ that are not
// normally present in Go (without explicitly opting in).
// For more discussion:
// https://groups.google.com/g/Golang-nuts/c/Jd9tlNc6jUE/m/Zo-7zIP_m3MJ?pli=1
spec.LDFlags = append(spec.LDFlags,
"-m", "i386pep",
"--image-base", "0x400000",
Expand Down
10 changes: 9 additions & 1 deletion compiler/calls.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -76,7 +76,15 @@ func (b *builder) createCall(fnType llvm.Type, fn llvm.Value, args []llvm.Value,
fragments := b.expandFormalParam(arg)
expanded = append(expanded, fragments...)
}
return b.CreateCall(fnType, fn, expanded, name)
call := b.CreateCall(fnType, fn, expanded, name)
if !fn.IsAFunction().IsNil() {
if cc := fn.FunctionCallConv(); cc != llvm.CCallConv {
// Set a different calling convention if needed.
// This is needed for GetModuleHandleExA on Windows, for example.
call.SetInstructionCallConv(cc)
}
}
return call
}

// createInvoke is like createCall but continues execution at the landing pad if
Expand Down
15 changes: 15 additions & 0 deletions compiler/llvm.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -452,6 +452,21 @@ func (b *builder) readStackPointer() llvm.Value {
return b.CreateCall(stacksave.GlobalValueType(), stacksave, nil, "")
}

// writeStackPointer emits a LLVM intrinsic call that updates the current stack
// pointer.
func (b *builder) writeStackPointer(sp llvm.Value) {
name := "llvm.stackrestore.p0"
if llvmutil.Version() < 18 {
name = "llvm.stackrestore" // backwards compatibility with LLVM 17 and below
}
stackrestore := b.mod.NamedFunction(name)
if stackrestore.IsNil() {
fnType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{b.dataPtrType}, false)
stackrestore = llvm.AddFunction(b.mod, name, fnType)
}
b.CreateCall(stackrestore.GlobalValueType(), stackrestore, []llvm.Value{sp}, "")
}

// createZExtOrTrunc lets the input value fit in the output type bits, by zero
// extending or truncating the integer.
func (b *builder) createZExtOrTrunc(value llvm.Value, t llvm.Type) llvm.Value {
Expand Down
6 changes: 6 additions & 0 deletions compiler/symbol.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -208,6 +208,12 @@ func (c *compilerContext) getFunction(fn *ssa.Function) (llvm.Type, llvm.Value)
// > circumstances, and should not be exposed to source languages.
llvmutil.AppendToGlobal(c.mod, "llvm.compiler.used", llvmFn)
}
case "GetModuleHandleExA", "GetProcAddress", "GetSystemInfo", "GetSystemTimeAsFileTime", "LoadLibraryExW", "QueryPerformanceCounter", "QueryPerformanceFrequency", "QueryUnbiasedInterruptTime", "SetEnvironmentVariableA", "Sleep", "SystemFunction036", "VirtualAlloc":
// On Windows we need to use a special calling convention for some
// external calls.
if c.GOOS == "windows" && c.GOARCH == "386" {
llvmFn.SetFunctionCallConv(llvm.X86StdcallCallConv)
}
}

// External/exported functions may not retain pointer values.
Expand Down
25 changes: 24 additions & 1 deletion compiler/syscall.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -268,6 +268,8 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
// The signature looks like this:
// func Syscall(trap, nargs, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)

isI386 := strings.HasPrefix(b.Triple, "i386-")

// Prepare input values.
var paramTypes []llvm.Type
var params []llvm.Value
Expand All @@ -285,11 +287,17 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
if setLastError.IsNil() {
llvmType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{b.ctx.Int32Type()}, false)
setLastError = llvm.AddFunction(b.mod, "SetLastError", llvmType)
if isI386 {
setLastError.SetFunctionCallConv(llvm.X86StdcallCallConv)
}
}
getLastError := b.mod.NamedFunction("GetLastError")
if getLastError.IsNil() {
llvmType := llvm.FunctionType(b.ctx.Int32Type(), nil, false)
getLastError = llvm.AddFunction(b.mod, "GetLastError", llvmType)
if isI386 {
getLastError.SetFunctionCallConv(llvm.X86StdcallCallConv)
}
}

// Now do the actual call. Pseudocode:
Expand All @@ -300,9 +308,24 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
// Note that SetLastError/GetLastError could be replaced with direct
// access to the thread control block, which is probably smaller and
// faster. The Go runtime does this in assembly.
b.CreateCall(setLastError.GlobalValueType(), setLastError, []llvm.Value{llvm.ConstNull(b.ctx.Int32Type())}, "")
// On windows/386, we also need to save/restore the stack pointer. I'm
// not entirely sure why this is needed, but without it these calls
// change the stack pointer leading to a crash soon after.
setLastErrorCall := b.CreateCall(setLastError.GlobalValueType(), setLastError, []llvm.Value{llvm.ConstNull(b.ctx.Int32Type())}, "")
var sp llvm.Value
if isI386 {
setLastErrorCall.SetInstructionCallConv(llvm.X86StdcallCallConv)
sp = b.readStackPointer()
}
syscallResult := b.CreateCall(llvmType, fnPtr, params, "")
if isI386 {
syscallResult.SetInstructionCallConv(llvm.X86StdcallCallConv)
b.writeStackPointer(sp)
}
errResult := b.CreateCall(getLastError.GlobalValueType(), getLastError, nil, "err")
if isI386 {
errResult.SetInstructionCallConv(llvm.X86StdcallCallConv)
}
if b.uintptrType != b.ctx.Int32Type() {
errResult = b.CreateZExt(errResult, b.uintptrType, "err.uintptr")
}
Expand Down
Loading