From 71c098f061e74c5214087728b028da4ff9db9679 Mon Sep 17 00:00:00 2001
From: google-yfyang <yfyang@google.com>
Date: Wed, 18 Jun 2025 13:57:16 -0400
Subject: [PATCH] emscripten related changes for llvm-libc

---
 libc/src/__support/StringUtil/platform_errors.h      | 2 +-
 libc/src/__support/StringUtil/tables/posix_errors.h  | 5 +++++
 libc/src/__support/StringUtil/tables/stdc_errors.h   | 5 +++++
 libc/src/__support/macros/properties/architectures.h | 4 ++++
 4 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/libc/src/__support/StringUtil/platform_errors.h b/libc/src/__support/StringUtil/platform_errors.h
index 32e8414b3e3d..5f83865482e7 100644
--- a/libc/src/__support/StringUtil/platform_errors.h
+++ b/libc/src/__support/StringUtil/platform_errors.h
@@ -9,7 +9,7 @@
 #ifndef LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_PLATFORM_ERRORS_H
 #define LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_PLATFORM_ERRORS_H
 
-#if defined(__linux__) || defined(__Fuchsia__)
+#if defined(__linux__) || defined(__Fuchsia__) || defined(__EMSCRIPTEN__)
 #include "tables/linux_platform_errors.h"
 #else
 #include "tables/minimal_platform_errors.h"
diff --git a/libc/src/__support/StringUtil/tables/posix_errors.h b/libc/src/__support/StringUtil/tables/posix_errors.h
index b21f28f0b132..031886dcc5cc 100644
--- a/libc/src/__support/StringUtil/tables/posix_errors.h
+++ b/libc/src/__support/StringUtil/tables/posix_errors.h
@@ -63,7 +63,12 @@ LIBC_INLINE_VAR constexpr MsgTable<76> POSIX_ERRORS = {
     MsgMapping(EPROTO, "Protocol error"),
     MsgMapping(EMULTIHOP, "Multihop attempted"),
     MsgMapping(EBADMSG, "Bad message"),
+#ifdef __EMSCRIPTEN__
+    // For now, match the musl string
+    MsgMapping(EOVERFLOW, "Value too large for data type"),
+#else
     MsgMapping(EOVERFLOW, "Value too large for defined data type"),
+#endif
     MsgMapping(ENOTSOCK, "Socket operation on non-socket"),
     MsgMapping(EDESTADDRREQ, "Destination address required"),
     MsgMapping(EMSGSIZE, "Message too long"),
diff --git a/libc/src/__support/StringUtil/tables/stdc_errors.h b/libc/src/__support/StringUtil/tables/stdc_errors.h
index a326616f20ef..9a23d0718ea1 100644
--- a/libc/src/__support/StringUtil/tables/stdc_errors.h
+++ b/libc/src/__support/StringUtil/tables/stdc_errors.h
@@ -16,7 +16,12 @@
 namespace LIBC_NAMESPACE_DECL {
 
 LIBC_INLINE_VAR constexpr const MsgTable<4> STDC_ERRORS = {
+#ifdef __EMSCRIPTEN__
+    // For now, match the musl name for errno 0.
+    MsgMapping(0, "No error information"),
+#else
     MsgMapping(0, "Success"),
+#endif
     MsgMapping(EDOM, "Numerical argument out of domain"),
     MsgMapping(ERANGE, "Numerical result out of range"),
     MsgMapping(EILSEQ, "Invalid or incomplete multibyte or wide character"),
diff --git a/libc/src/__support/macros/properties/architectures.h b/libc/src/__support/macros/properties/architectures.h
index c88956ff4114..817ced4e95c2 100644
--- a/libc/src/__support/macros/properties/architectures.h
+++ b/libc/src/__support/macros/properties/architectures.h
@@ -41,6 +41,10 @@
 #define LIBC_TARGET_ARCH_IS_ARM
 #endif
 
+#if defined(__wasm__)
+#define LIBC_TARGET_ARCH_IS_WASM
+#endif
+
 #if defined(__aarch64__) || defined(__arm64__) || defined(_M_ARM64)
 #define LIBC_TARGET_ARCH_IS_AARCH64
 #endif
-- 
2.50.0.rc2.701.gf1e915cc24-goog