libcxx: update to LLVM 18

release/18.x branch, commit 78b99c73ee4b96fe9ce0e294d4632326afb2db42

This adds the flag `-D_LIBCPP_HARDENING_MODE` which is determined based
on the Zig optimization mode.

This commit also fixes libunwind, libcxx, and libcxxabi to properly
report sub compilation errors.

1 files changed, 12 insertions, 21 deletions

diff --git a/lib/libcxx/src/charconv.cpp b/lib/libcxx/src/charconv.cpp
index aa52220413..4fd7a2c2c0 100644
--- a/lib/libcxx/src/charconv.cpp
+++ b/lib/libcxx/src/charconv.cpp
@@ -15,22 +15,13 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 #ifndef _LIBCPP_ABI_DO_NOT_EXPORT_TO_CHARS_BASE_10
 
-namespace __itoa
-{
+namespace __itoa {
 
-_LIBCPP_EXPORTED_FROM_ABI char*
-__u32toa(uint32_t value, char* buffer) noexcept
-{
-  return __base_10_u32(buffer, value);
-}
+_LIBCPP_EXPORTED_FROM_ABI char* __u32toa(uint32_t value, char* buffer) noexcept { return __base_10_u32(buffer, value); }
 
-_LIBCPP_EXPORTED_FROM_ABI char*
-__u64toa(uint64_t value, char* buffer) noexcept
-{
-  return __base_10_u64(buffer, value);
-}
+_LIBCPP_EXPORTED_FROM_ABI char* __u64toa(uint64_t value, char* buffer) noexcept { return __base_10_u64(buffer, value); }
 
-}  // namespace __itoa
+} // namespace __itoa
 
 #endif // _LIBCPP_ABI_DO_NOT_EXPORT_TO_CHARS_BASE_10
 
@@ -51,8 +42,8 @@ to_chars_result to_chars(char* __first, char* __last, double __value) {
 }
 
 to_chars_result to_chars(char* __first, char* __last, long double __value) {
-  return _Floating_to_chars<_Floating_to_chars_overload::_Plain>(__first, __last, static_cast<double>(__value),
-                                                                 chars_format{}, 0);
+  return _Floating_to_chars<_Floating_to_chars_overload::_Plain>(
+      __first, __last, static_cast<double>(__value), chars_format{}, 0);
 }
 
 to_chars_result to_chars(char* __first, char* __last, float __value, chars_format __fmt) {
@@ -64,18 +55,18 @@ to_chars_result to_chars(char* __first, char* __last, double __value, chars_form
 }
 
 to_chars_result to_chars(char* __first, char* __last, long double __value, chars_format __fmt) {
-  return _Floating_to_chars<_Floating_to_chars_overload::_Format_only>(__first, __last, static_cast<double>(__value),
-                                                                       __fmt, 0);
+  return _Floating_to_chars<_Floating_to_chars_overload::_Format_only>(
+      __first, __last, static_cast<double>(__value), __fmt, 0);
 }
 
 to_chars_result to_chars(char* __first, char* __last, float __value, chars_format __fmt, int __precision) {
-  return _Floating_to_chars<_Floating_to_chars_overload::_Format_precision>(__first, __last, __value, __fmt,
-                                                                            __precision);
+  return _Floating_to_chars<_Floating_to_chars_overload::_Format_precision>(
+      __first, __last, __value, __fmt, __precision);
 }
 
 to_chars_result to_chars(char* __first, char* __last, double __value, chars_format __fmt, int __precision) {
-  return _Floating_to_chars<_Floating_to_chars_overload::_Format_precision>(__first, __last, __value, __fmt,
-                                                                            __precision);
+  return _Floating_to_chars<_Floating_to_chars_overload::_Format_precision>(
+      __first, __last, __value, __fmt, __precision);
 }
 
 to_chars_result to_chars(char* __first, char* __last, long double __value, chars_format __fmt, int __precision) {