Files
tinygo/compiler
deadprogram ddacdfacd5 compiler, runtime: fix SyscallN handling for Windows on Go 1.26+
Go 1.26 changed all Windows syscall wrappers in zsyscall_windows.go
to use SyscallN instead of fixed-argument Syscall/Syscall6/etc. The
SyscallN function now has a body that calls an unexported syscalln
function (provided by runtime via //go:linkname).

TinyGo's existing createSyscall compiler builtin used call.Args[2:]
to extract syscall arguments, but for variadic SyscallN the SSA
representation passes args as a slice value (not individual args),
causing call.Args[2:] to be empty -- resulting in zero arguments
being passed to Windows API calls and 0xc0000005 access violations.

Fix this by:
1. Excluding syscall.SyscallN from builtin interception, letting
   Go 1.26's function body compile normally (it calls syscalln)
2. Adding a new createSyscalln compiler builtin that intercepts
   syscall.syscalln and correctly handles the variadic slice:
   - Generates a switch on the arg count n (0-18 cases)
   - Each case loads args from the slice via GEP/Load
   - Wraps calls with SetLastError(0)/GetLastError() as before
   - Handles i386 stdcall conventions
3. Adding runtime stubs for both Go versions:
   - go1.26: syscall.syscalln stub (body intercepted by compiler)
   - pre-go1.26: syscall.SyscallN stub (linker satisfaction)
2026-04-11 12:38:36 +01:00
..
2025-02-25 14:41:42 +01:00
2021-09-27 15:47:12 +02:00
2023-10-01 18:32:15 +02:00
2026-04-05 14:14:55 +02:00
2026-04-05 14:14:55 +02:00
2026-01-05 15:10:31 -05:00