Skip to content

Revert "[libc] wchar string conversion functions mb to wc" #150549

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

Jump to bottom
Merged
merged 1 commit into from
Jul 24, 2025
Merged

Revert "[libc] wchar string conversion functions mb to wc" #150549

merged 1 commit into from
Jul 24, 2025

Conversation

sribee8
Copy link
Contributor

@sribee8 sribee8 commented Jul 24, 2025

Reverts #149423

Failing nullptr crash when using sanitizer

@llvmbot llvmbot added the libc label Jul 24, 2025
@llvmbot
Copy link
Member

llvmbot commented Jul 24, 2025

@llvm/pr-subscribers-libc

Author: None (sribee8)

Changes

Reverts llvm/llvm-project#149423

Failing nullptr crash when using sanitizer

Patch is 36.72 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/150549.diff

15 Files Affected:

  • (modified) libc/config/linux/x86_64/entrypoints.txt (-3)
  • (modified) libc/include/wchar.yaml (-27)
  • (modified) libc/src/__support/wchar/CMakeLists.txt (+8-25)
  • (removed) libc/src/__support/wchar/mbsnrtowcs.h (-66)
  • (modified) libc/src/wchar/CMakeLists.txt (-48)
  • (removed) libc/src/wchar/mbsnrtowcs.cpp (-39)
  • (removed) libc/src/wchar/mbsnrtowcs.h (-24)
  • (removed) libc/src/wchar/mbsrtowcs.cpp (-39)
  • (removed) libc/src/wchar/mbsrtowcs.h (-24)
  • (removed) libc/src/wchar/mbstowcs.cpp (-38)
  • (removed) libc/src/wchar/mbstowcs.h (-22)
  • (modified) libc/test/src/wchar/CMakeLists.txt (+1-47)
  • (removed) libc/test/src/wchar/mbsnrtowcs_test.cpp (-211)
  • (removed) libc/test/src/wchar/mbsrtowcs_test.cpp (-184)
  • (removed) libc/test/src/wchar/mbstowcs_test.cpp (-170)
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 5af11db427310..e8f59c9d5cd73 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -1266,9 +1266,6 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.wchar.mbrlen
     libc.src.wchar.mbrtowc
     libc.src.wchar.mbtowc
-    libc.src.wchar.mbstowcs
-    libc.src.wchar.mbsrtowcs
-    libc.src.wchar.mbsnrtowcs
     libc.src.wchar.wcrtomb
     libc.src.wchar.wctomb
     libc.src.wchar.wcstombs
diff --git a/libc/include/wchar.yaml b/libc/include/wchar.yaml
index fbcbf1ce06b80..0285f1924a2fa 100644
--- a/libc/include/wchar.yaml
+++ b/libc/include/wchar.yaml
@@ -53,33 +53,6 @@ functions:
       - type: wchar_t *__restrict
       - type: const char *__restrict
       - type: size_t
-  - name: mbsnrtowcs
-    standards:
-      - stdc
-    return_type: size_t
-    arguments:
-      - type: wchar_t *__restrict
-      - type: const char **__restrict
-      - type: size_t
-      - type: size_t
-      - type: mbstate_t *__restrict
-  - name: mbsrtowcs
-    standards:
-      - stdc
-    return_type: size_t
-    arguments:
-      - type: wchar_t *__restrict
-      - type: const char **__restrict
-      - type: size_t
-      - type: mbstate_t *__restrict
-  - name: mbstowcs
-    standards:
-      - stdc
-    return_type: size_t
-    arguments:
-      - type: wchar_t *__restrict
-      - type: const char *__restrict
-      - type: size_t
   - name: mblen
     standards:
       - stdc
diff --git a/libc/src/__support/wchar/CMakeLists.txt b/libc/src/__support/wchar/CMakeLists.txt
index aed1d53bdf522..e363ad397079c 100644
--- a/libc/src/__support/wchar/CMakeLists.txt
+++ b/libc/src/__support/wchar/CMakeLists.txt
@@ -60,31 +60,14 @@ add_object_library(
   SRCS
     mbrtowc.cpp
   DEPENDS
-    libc.hdr.errno_macros
-    libc.hdr.types.wchar_t
-    libc.hdr.types.size_t
-    libc.src.__support.common
-    libc.src.__support.error_or
-    libc.src.__support.macros.config
-    .character_converter
-    .mbstate
-)
-
-add_header_library(
-  mbsnrtowcs
-  HDRS
-    mbsnrtowcs.h
-  DEPENDS
-    libc.hdr.errno_macros
-    libc.hdr.types.wchar_t
-    libc.hdr.types.size_t
-    libc.src.__support.common
-    libc.src.__support.error_or
-    libc.src.__support.macros.config
-    libc.src.__support.macros.null_check
-    .character_converter
-    .mbstate
-    .string_converter
+  libc.hdr.errno_macros
+  libc.hdr.types.wchar_t
+  libc.hdr.types.size_t
+  libc.src.__support.common
+  libc.src.__support.error_or
+  libc.src.__support.macros.config
+  .character_converter
+  .mbstate
 )
 
 add_header_library(
diff --git a/libc/src/__support/wchar/mbsnrtowcs.h b/libc/src/__support/wchar/mbsnrtowcs.h
deleted file mode 100644
index 54e315210d95c..0000000000000
--- a/libc/src/__support/wchar/mbsnrtowcs.h
+++ /dev/null
@@ -1,66 +0,0 @@
-//===-- Implementation for mbsnrtowcs function ------------------*- C++ -*-===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIBC_SRC___SUPPORT_WCHAR_MBSNRTOWCS_H
-#define LLVM_LIBC_SRC___SUPPORT_WCHAR_MBSNRTOWCS_H
-
-#include "hdr/errno_macros.h"
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/common.h"
-#include "src/__support/error_or.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/macros/null_check.h"
-#include "src/__support/wchar/character_converter.h"
-#include "src/__support/wchar/mbstate.h"
-#include "src/__support/wchar/string_converter.h"
-
-namespace LIBC_NAMESPACE_DECL {
-namespace internal {
-
-LIBC_INLINE static ErrorOr<size_t> mbsnrtowcs(wchar_t *__restrict dst,
-                                              const char **__restrict src,
-                                              size_t nmc, size_t len,
-                                              mbstate *__restrict ps) {
-  LIBC_CRASH_ON_NULLPTR(src);
-  // Checking if mbstate is valid
-  CharacterConverter char_conv(ps);
-  if (!char_conv.isValidState())
-    return Error(EINVAL);
-
-  StringConverter<char8_t> str_conv(reinterpret_cast<const char8_t *>(*src), ps,
-                                    len, nmc);
-  size_t dst_idx = 0;
-  ErrorOr<char32_t> converted = str_conv.popUTF32();
-  while (converted.has_value()) {
-    if (dst != nullptr)
-      dst[dst_idx] = converted.value();
-    // null terminator should not be counted in return value
-    if (converted.value() == L'\0') {
-      if (dst != nullptr)
-        *src = nullptr;
-      return dst_idx;
-    }
-    dst_idx++;
-    converted = str_conv.popUTF32();
-  }
-
-  if (converted.error() == -1) { // if we hit conversion limit
-    if (dst != nullptr)
-      *src += str_conv.getSourceIndex();
-    return dst_idx;
-  }
-
-  return Error(converted.error());
-}
-
-} // namespace internal
-
-} // namespace LIBC_NAMESPACE_DECL
-
-#endif // LLVM_LIBC_SRC___SUPPORT_WCHAR_MBSNRTOWCS_H
diff --git a/libc/src/wchar/CMakeLists.txt b/libc/src/wchar/CMakeLists.txt
index aca6634d45e7f..43f44a941d451 100644
--- a/libc/src/wchar/CMakeLists.txt
+++ b/libc/src/wchar/CMakeLists.txt
@@ -169,54 +169,6 @@ add_entrypoint_object(
     libc.src.__support.wchar.mbstate
 )
 
-add_entrypoint_object(
-  mbstowcs
-  SRCS
-    mbstowcs.cpp
-  HDRS
-    mbstowcs.h
-  DEPENDS
-    libc.hdr.types.size_t
-    libc.hdr.types.wchar_t
-    libc.src.__support.common
-    libc.src.__support.macros.config
-    libc.src.__support.libc_errno
-    libc.src.__support.wchar.mbstate
-    libc.src.__support.wchar.mbsnrtowcs
-)
-
-add_entrypoint_object(
-  mbsrtowcs
-  SRCS
-    mbsrtowcs.cpp
-  HDRS
-    mbsrtowcs.h
-  DEPENDS
-    libc.hdr.types.size_t
-    libc.hdr.types.wchar_t
-    libc.src.__support.common
-    libc.src.__support.macros.config
-    libc.src.__support.libc_errno
-    libc.src.__support.wchar.mbstate
-    libc.src.__support.wchar.mbsnrtowcs
-)
-
-add_entrypoint_object(
-  mbsnrtowcs
-  SRCS
-    mbsnrtowcs.cpp
-  HDRS
-    mbsnrtowcs.h
-  DEPENDS
-    libc.hdr.types.size_t
-    libc.hdr.types.wchar_t
-    libc.src.__support.common
-    libc.src.__support.macros.config
-    libc.src.__support.libc_errno
-    libc.src.__support.wchar.mbstate
-    libc.src.__support.wchar.mbsnrtowcs
-)
-
 add_entrypoint_object(
   wcstombs
   SRCS
diff --git a/libc/src/wchar/mbsnrtowcs.cpp b/libc/src/wchar/mbsnrtowcs.cpp
deleted file mode 100644
index 28e0ff31b26c4..0000000000000
--- a/libc/src/wchar/mbsnrtowcs.cpp
+++ /dev/null
@@ -1,39 +0,0 @@
-//===-- Implementation of mbsnrtowcs --------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "src/wchar/mbsnrtowcs.h"
-
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/common.h"
-#include "src/__support/libc_errno.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/wchar/mbsnrtowcs.h"
-#include "src/__support/wchar/mbstate.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-LLVM_LIBC_FUNCTION(size_t, mbsnrtowcs,
-                   (wchar_t *__restrict dst, const char **__restrict src,
-                    size_t nmc, size_t len, mbstate_t *__restrict ps)) {
-  static internal::mbstate internal_mbstate;
-  // If destination is null, ignore len
-  len = dst == nullptr ? SIZE_MAX : len;
-  auto ret = internal::mbsnrtowcs(
-      dst, src, nmc, len,
-      ps == nullptr ? &internal_mbstate
-                    : reinterpret_cast<internal::mbstate *>(ps));
-  if (!ret.has_value()) {
-    // Encoding failure
-    libc_errno = ret.error();
-    return -1;
-  }
-  return ret.value();
-}
-
-} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/wchar/mbsnrtowcs.h b/libc/src/wchar/mbsnrtowcs.h
deleted file mode 100644
index 0d66b952db01a..0000000000000
--- a/libc/src/wchar/mbsnrtowcs.h
+++ /dev/null
@@ -1,24 +0,0 @@
-//===-- Implementation header for mbsnrtowcs ------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIBC_SRC_WCHAR_MBSNRTOWCS_H
-#define LLVM_LIBC_SRC_WCHAR_MBSNRTOWCS_H
-
-#include "hdr/types/mbstate_t.h"
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/macros/config.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-size_t mbsnrtowcs(wchar_t *__restrict dst, const char **__restrict src,
-                  size_t nmc, size_t len, mbstate_t *__restrict ps);
-
-} // namespace LIBC_NAMESPACE_DECL
-
-#endif // LLVM_LIBC_SRC_WCHAR_MBSNRTOWCS_H
diff --git a/libc/src/wchar/mbsrtowcs.cpp b/libc/src/wchar/mbsrtowcs.cpp
deleted file mode 100644
index 82ca25a3d863d..0000000000000
--- a/libc/src/wchar/mbsrtowcs.cpp
+++ /dev/null
@@ -1,39 +0,0 @@
-//===-- Implementation of mbsrtowcs ---------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "src/wchar/mbsrtowcs.h"
-
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/common.h"
-#include "src/__support/libc_errno.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/wchar/mbsnrtowcs.h"
-#include "src/__support/wchar/mbstate.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-LLVM_LIBC_FUNCTION(size_t, mbsrtowcs,
-                   (wchar_t *__restrict dst, const char **__restrict src,
-                    size_t len, mbstate_t *__restrict ps)) {
-  static internal::mbstate internal_mbstate;
-  // If destination is null, ignore len
-  len = dst == nullptr ? SIZE_MAX : len;
-  auto ret = internal::mbsnrtowcs(
-      dst, src, SIZE_MAX, len,
-      ps == nullptr ? &internal_mbstate
-                    : reinterpret_cast<internal::mbstate *>(ps));
-  if (!ret.has_value()) {
-    // Encoding failure
-    libc_errno = ret.error();
-    return -1;
-  }
-  return ret.value();
-}
-
-} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/wchar/mbsrtowcs.h b/libc/src/wchar/mbsrtowcs.h
deleted file mode 100644
index f8d4cc26e63ae..0000000000000
--- a/libc/src/wchar/mbsrtowcs.h
+++ /dev/null
@@ -1,24 +0,0 @@
-//===-- Implementation header for mbsrtowcs -------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIBC_SRC_WCHAR_MBSRTOWCS_H
-#define LLVM_LIBC_SRC_WCHAR_MBSRTOWCS_H
-
-#include "hdr/types/mbstate_t.h"
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/macros/config.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-size_t mbsrtowcs(wchar_t *__restrict dst, const char **__restrict src,
-                 size_t len, mbstate_t *__restrict ps);
-
-} // namespace LIBC_NAMESPACE_DECL
-
-#endif // LLVM_LIBC_SRC_WCHAR_MBSRTOWCS_H
diff --git a/libc/src/wchar/mbstowcs.cpp b/libc/src/wchar/mbstowcs.cpp
deleted file mode 100644
index 1a3232847fa71..0000000000000
--- a/libc/src/wchar/mbstowcs.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//===-- Implementation of mbstowcs ----------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "src/wchar/mbstowcs.h"
-
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/common.h"
-#include "src/__support/libc_errno.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/wchar/mbsnrtowcs.h"
-#include "src/__support/wchar/mbstate.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-LLVM_LIBC_FUNCTION(size_t, mbstowcs,
-                   (wchar_t *__restrict pwcs, const char *__restrict s,
-                    size_t n)) {
-  // If destination is null, ignore n
-  n = pwcs == nullptr ? SIZE_MAX : n;
-  static internal::mbstate internal_mbstate;
-  const char *temp = s;
-  auto ret = internal::mbsnrtowcs(pwcs, &temp, SIZE_MAX, n, &internal_mbstate);
-
-  if (!ret.has_value()) {
-    // Encoding failure
-    libc_errno = ret.error();
-    return -1;
-  }
-  return ret.value();
-}
-
-} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/wchar/mbstowcs.h b/libc/src/wchar/mbstowcs.h
deleted file mode 100644
index 7d08a838b2324..0000000000000
--- a/libc/src/wchar/mbstowcs.h
+++ /dev/null
@@ -1,22 +0,0 @@
-//===-- Implementation header for mbstowcs --------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIBC_SRC_WCHAR_MBSTOWCS_H
-#define LLVM_LIBC_SRC_WCHAR_MBSTOWCS_H
-
-#include "hdr/types/size_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/macros/config.h"
-
-namespace LIBC_NAMESPACE_DECL {
-
-size_t mbstowcs(wchar_t *__restrict pwcs, const char *__restrict s, size_t n);
-
-} // namespace LIBC_NAMESPACE_DECL
-
-#endif // LLVM_LIBC_SRC_WCHAR_MBSTOWCS_H
diff --git a/libc/test/src/wchar/CMakeLists.txt b/libc/test/src/wchar/CMakeLists.txt
index 48d9c48f2380c..f420ecc465a53 100644
--- a/libc/test/src/wchar/CMakeLists.txt
+++ b/libc/test/src/wchar/CMakeLists.txt
@@ -75,19 +75,6 @@ add_libc_test(
     libc.test.UnitTest.ErrnoCheckingTest
 )
 
-add_libc_test(
-  mbstowcs_test
-  SUITE
-    libc_wchar_unittests
-  SRCS
-    mbstowcs_test.cpp
-  DEPENDS
-    libc.src.__support.libc_errno
-    libc.src.wchar.mbstowcs
-    libc.hdr.types.wchar_t
-    libc.test.UnitTest.ErrnoCheckingTest
-)
-
 add_libc_test(
   mblen_test
   SUITE
@@ -100,22 +87,6 @@ add_libc_test(
     libc.test.UnitTest.ErrnoCheckingTest
 )
 
-add_libc_test(
-  mbsrtowcs_test
-  SUITE
-    libc_wchar_unittests
-  SRCS
-    mbsrtowcs_test.cpp
-  DEPENDS
-    libc.src.__support.libc_errno
-    libc.src.__support.wchar.mbstate
-    libc.src.string.memset
-    libc.src.wchar.mbsrtowcs
-    libc.hdr.types.mbstate_t
-    libc.hdr.types.wchar_t
-    libc.test.UnitTest.ErrnoCheckingTest
-)
-
 add_libc_test(
   mbrlen_test
   SUITE
@@ -126,25 +97,8 @@ add_libc_test(
     libc.src.__support.libc_errno
     libc.src.__support.wchar.mbstate
     libc.src.string.memset
-    libc.src.wchar.mbsrlen
-    libc.hdr.types.mbstate_t
-    libc.hdr.types.wchar_t
-    libc.test.UnitTest.ErrnoCheckingTest
-)
-
-add_libc_test(
-  mbsnrtowcs_test
-  SUITE
-    libc_wchar_unittests
-  SRCS
-    mbsnrtowcs_test.cpp
-  DEPENDS
-    libc.src.__support.libc_errno
-    libc.src.__support.wchar.mbstate
-    libc.src.string.memset
-    libc.src.wchar.mbsnrtowcs
+    libc.src.wchar.mbrlen
     libc.hdr.types.mbstate_t
-    libc.hdr.types.wchar_t
     libc.test.UnitTest.ErrnoCheckingTest
 )
 
diff --git a/libc/test/src/wchar/mbsnrtowcs_test.cpp b/libc/test/src/wchar/mbsnrtowcs_test.cpp
deleted file mode 100644
index d1232e36a5880..0000000000000
--- a/libc/test/src/wchar/mbsnrtowcs_test.cpp
+++ /dev/null
@@ -1,211 +0,0 @@
-//===-- Unittests for mbsetowcs -------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include "hdr/types/mbstate_t.h"
-#include "hdr/types/wchar_t.h"
-#include "src/__support/libc_errno.h"
-#include "src/__support/wchar/mbstate.h"
-#include "src/string/memset.h"
-#include "src/wchar/mbsnrtowcs.h"
-#include "test/UnitTest/ErrnoCheckingTest.h"
-#include "test/UnitTest/Test.h"
-
-using LlvmLibcMBSNRToWCSTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
-
-TEST_F(LlvmLibcMBSNRToWCSTest, OneByteOneChar) {
-  const char *ch = "A";
-  const char *original = ch;
-  wchar_t dest[2];
-  mbstate_t mb;
-  LIBC_NAMESPACE::memset(&mb, 0, sizeof(mbstate_t));
-  size_t n = LIBC_NAMESPACE::mbsnrtowcs(dest, &ch, 1, 1, &mb);
-  ASSERT_EQ(static_cast<char>(*dest), 'A');
-  ASSERT_EQ(static_cast<int>(n), 1);
-  // Should point to null terminator now
-  ASSERT_EQ(ch, original + 1);
-  ASSERT_ERRNO_SUCCESS();
-
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 1, &ch, 1, 1, &mb);
-  ASSERT_EQ(static_cast<char>(dest[1]), '\0');
-  // Should not include null terminator
-  ASSERT_EQ(static_cast<int>(n), 0);
-  // Should now be a nullptr
-  ASSERT_EQ(ch, nullptr);
-  ASSERT_ERRNO_SUCCESS();
-}
-
-TEST_F(LlvmLibcMBSNRToWCSTest, FourByteOneChar) {
-  const char *src = "\xf0\x9f\x98\xb9"; // laughing cat emoji 😹
-  const char *original = src;
-  wchar_t dest[2];
-  mbstate_t mb;
-  LIBC_NAMESPACE::memset(&mb, 0, sizeof(mbstate_t));
-  // Not enough bytes for the full character
-  size_t n = LIBC_NAMESPACE::mbsnrtowcs(dest, &src, 3, 2, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<int>(n), 0);
-  ASSERT_EQ(src, original + 3);
-  // Needs 2 more bytes (last byte of cat + null terminator)
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest, &src, 2, 2, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  // Does not include null terminator
-  ASSERT_EQ(static_cast<int>(n), 1);
-  ASSERT_EQ(src, nullptr);
-  ASSERT_EQ(static_cast<int>(dest[0]), 128569);
-  ASSERT_TRUE(dest[1] == L'\0');
-}
-
-TEST_F(LlvmLibcMBSNRToWCSTest, MixedNumberOfBytes) {
-  // 'A', sigma symbol 'Σ', recycling symbol '♻', laughing cat emoji '😹'
-  const char *src = "A\xce\xa3\xe2\x99\xbb\xf0\x9f\x98\xb9";
-  const char *original = src;
-  wchar_t dest[5];
-  mbstate_t mb;
-  LIBC_NAMESPACE::memset(&mb, 0, sizeof(mbstate_t));
-
-  // Read 'A'
-  size_t n = LIBC_NAMESPACE::mbsnrtowcs(dest, &src, 1, 1, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<char>(dest[0]), 'A');
-  ASSERT_EQ(static_cast<int>(n), 1);
-  ASSERT_EQ(src, original + 1);
-
-  // Read sigma 'Σ'
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 1, &src, 2, 1, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<int>(dest[1]), 931);
-  ASSERT_EQ(static_cast<int>(n), 1);
-  ASSERT_EQ(src, original + 3);
-
-  // Read recycling '♻'
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 2, &src, 2, 5, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<int>(n), 0);
-  ASSERT_EQ(src, original + 5);
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 2, &src, 1, 1, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<int>(n), 1);
-  ASSERT_EQ(src, original + 6);
-  ASSERT_EQ(static_cast<int>(dest[2]), 9851);
-
-  // Read laughing cat emoji '😹'
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 3, &src, 4, 5, &mb);
-  ASSERT_ERRNO_SUCCESS();
-  ASSERT_EQ(static_cast<int>(n), 1);
-  ASSERT_EQ(src, original + 10);
-  ASSERT_EQ(static_cast<int>(dest[3]), 128569);
-
-  n = LIBC_NAMESPACE::mbsnrtowcs(dest + 4, &src, 4, 4, nullptr);
-  ASSERT_TRUE(dest[4] == L'\0');
-  ASSERT_ERRNO_SUCCESS();
-  // Should not count null terminator in number
-  ASSERT_EQ(static_cast<int>(n), 0);
-  // Should now be a nullptr
-  ASSERT_EQ(src, nullptr);
-}
-
-TEST_F(LlvmLibcMBSNRToWCSTest, ReadLessThanStringLength) {
-  // Four laughing cat emojis "😹😹😹😹"
-  const char *src =
-      "\xf0\x9f\x98\xb9\xf0\x9f\x98\xb9\xf0\x9f\x98\xb9\xf0\x9f\x98\xb9";
-  const char *original = src;
-  wchar_t dest[5] = {L'a', L'b', L'c', L'd', L'e'};
-  size_t n = LIBC_NAMESPACE::mbsnrtowcs(dest, &src, 100, 3, nullptr);
-  ASSERT_ERRNO_SUCCESS();
-  // Should have read 3 emojis
-  ASSERT_EQ(static_cast<int...
[truncated]

@sribee8 sribee8 merged commit 42b101d into main Jul 24, 2025
14 of 21 checks passed
@sribee8 sribee8 deleted the revert-149423-mbstowcs-implementation branch July 24, 2025 23:39
mahesh-attarde pushed a commit to mahesh-attarde/llvm-project that referenced this pull request Jul 28, 2025
@sribee8 @mahesh-attarde
Revert "[libc] wchar string conversion functions mb to wc" (llvm#150549)
3ca08ac 
Reverts llvm#149423

Failing nullptr crash when using sanitizer
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers
No reviews
Assignees
No one assigned
Labels
libc
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.
2 participants
@sribee8 @llvmbot