[libc++] Add macros for try/catch and rethrow

[philnik777]

This makes code using try/catch blocks significantly more readable, since we avoid a bunch of #if _LIBCPP_HAS_EXCEPTIONS.

[github-actions]

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff a2042521a0387d7d7b80b2987f4b21f5a50bc7bb cd8a8f667aff3fa310caf8b09e9cf866d3fde41f --extensions ,cpp,h -- libcxx/include/__config libcxx/include/__flat_map/flat_map.h libcxx/include/__hash_table libcxx/include/__iterator/counted_iterator.h libcxx/include/__memory/shared_ptr.h libcxx/include/__memory/uninitialized_algorithms.h libcxx/include/__ostream/basic_ostream.h libcxx/include/__ostream/print.h libcxx/include/__pstl/backends/libdispatch.h libcxx/include/__split_buffer libcxx/include/__vector/vector.h libcxx/include/__vector/vector_bool.h libcxx/include/deque libcxx/include/forward_list libcxx/include/fstream libcxx/include/future libcxx/include/iomanip libcxx/include/istream libcxx/include/list libcxx/include/sstream libcxx/include/string libcxx/include/syncstream libcxx/include/valarray libcxx/include/variant libcxx/src/filesystem/error.h libcxx/src/filesystem/format_string.h libcxx/src/locale.cpp

View the diff from clang-format here.

diff --git a/libcxx/include/__config b/libcxx/include/__config
index b318369f6a..f5373ba255 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -1233,7 +1233,7 @@ typedef __char32_t char32_t;
 
 #  if _LIBCPP_HAS_EXCEPTIONS
 #    define _LIBCPP_TRY try
-#    define _LIBCPP_CATCH(...) catch(__VA_ARGS__)
+#    define _LIBCPP_CATCH(...) catch (__VA_ARGS__)
 #    define _LIBCPP_RETHROW throw
 #  else
 #    define _LIBCPP_TRY if (true)
diff --git a/libcxx/include/__flat_map/flat_map.h b/libcxx/include/__flat_map/flat_map.h
index a511f38799..d5f66600be 100644
--- a/libcxx/include/__flat_map/flat_map.h
+++ b/libcxx/include/__flat_map/flat_map.h
@@ -1144,7 +1144,7 @@ private:
       } else {
         // In this case, we know the values are just like before we attempted emplacement,
         // and we also know that the keys have been emplaced successfully. Just roll back the keys.
-        _LIBCPP_TRY {
+      _LIBCPP_TRY {
           __containers_.keys.erase(__key_it);
         } _LIBCPP_CATCH(...) {
           // Now things are funky for real. We're failing to rollback the keys.
diff --git a/libcxx/include/__ostream/basic_ostream.h b/libcxx/include/__ostream/basic_ostream.h
index d19869621d..e9431f6ca1 100644
--- a/libcxx/include/__ostream/basic_ostream.h
+++ b/libcxx/include/__ostream/basic_ostream.h
@@ -584,7 +584,8 @@ basic_ostream<_CharT, _Traits>& basic_ostream<_CharT, _Traits>::write(const char
       if (this->rdbuf()->sputn(__s, __n) != __n)
         this->setstate(ios_base::badbit);
     }
-  } _LIBCPP_CATCH(...) {
+  }
+  _LIBCPP_CATCH(...) {
     this->__set_badbit_and_consider_rethrow();
   }
   return *this;
diff --git a/libcxx/include/__vector/vector.h b/libcxx/include/__vector/vector.h
index 19c8964b95..29562d4ff3 100644
--- a/libcxx/include/__vector/vector.h
+++ b/libcxx/include/__vector/vector.h
@@ -1274,7 +1274,7 @@ vector<_Tp, _Allocator>::__insert_with_sentinel(const_iterator __position, _Inpu
       reserve(__recommend(size() + __v.size()));
       __p        = this->__begin_ + __old_p;
       __old_last = this->__begin_ + __old_size;
-    } _LIBCPP_CATCH (...) {
+    } _LIBCPP_CATCH(...) {
       erase(__make_iter(__old_last), end());
       _LIBCPP_RETHROW;
     }
diff --git a/libcxx/include/future b/libcxx/include/future
index 67060941d6..f94a2d8298 100644
--- a/libcxx/include/future
+++ b/libcxx/include/future
@@ -867,7 +867,7 @@ void __async_assoc_state<void, _Fp>::__execute() {
   _LIBCPP_TRY {
     __func_();
     this->set_value();
-  } _LIBCPP_CATCH (...) {
+  } _LIBCPP_CATCH(...) {
     this->set_exception(current_exception());
   }
 }
@@ -1737,7 +1737,7 @@ void packaged_task<void(_ArgTypes...)>::operator()(_ArgTypes... __args) {
   _LIBCPP_TRY {
     __f_(std::forward<_ArgTypes>(__args)...);
     __p_.set_value();
-  } _LIBCPP_CATCH (...) {
+  } _LIBCPP_CATCH(...) {
     __p_.set_exception(current_exception());
   }
 }
diff --git a/libcxx/include/istream b/libcxx/include/istream
index 130182c0ee..bd20bea188 100644
--- a/libcxx/include/istream
+++ b/libcxx/include/istream
@@ -833,7 +833,7 @@ typename basic_istream<_CharT, _Traits>::int_type basic_istream<_CharT, _Traits>
       __r = this->rdbuf()->sgetc();
       if (traits_type::eq_int_type(__r, traits_type::eof()))
         __state |= ios_base::eofbit;
-    } _LIBCPP_CATCH (...) {
+    } _LIBCPP_CATCH(...) {
       __state |= ios_base::badbit;
       this->__setstate_nothrow(__state);
       if (this->exceptions() & ios_base::badbit) {
diff --git a/libcxx/include/string b/libcxx/include/string
index 7604a51ca4..3efc69edba 100644
--- a/libcxx/include/string
+++ b/libcxx/include/string
@@ -2486,7 +2486,7 @@ basic_string<_CharT, _Traits, _Allocator>::__init_with_size(_InputIterator __fir
   _LIBCPP_TRY {
     auto __end = __copy_non_overlapping_range(__first, __last, std::__to_address(__p));
     traits_type::assign(*__end, value_type());
-  } _LIBCPP_CATCH (...) {
+  } _LIBCPP_CATCH(...) {
     if (__is_long())
       __alloc_traits::deallocate(__alloc_, __get_long_pointer(), __get_long_cap());
     _LIBCPP_RETHROW;