get everything running with -fno-exceptions (#1556)

Author: ericniebler

.clang-format

@@ -152,6 +152,10 @@ SpacesInConditionalStatement: false
 SpacesInContainerLiterals: true
 SpacesInParentheses: false
 Standard: c++20
+StatementMacros: [
+  'STDEXEC_IF_HOST',
+  'STDEXEC_IF_DEVICE',
+]
 TabWidth: 0
 TypenameMacros: []
 UseTab: Never

examples/algorithms/retry.hpp

@@ -91,10 +91,11 @@ struct _op {
   }
 
   void _retry() noexcept {
-    try {
+    STDEXEC_TRY {
       o_.emplace(_connect()); // potentially throwing
       stdexec::start(*o_);
-    } catch (...) {
+    }
+    STDEXEC_CATCH_ALL {
       stdexec::set_error(static_cast<R&&>(r_), std::current_exception());
     }
   }

examples/algorithms/then.hpp

@@ -41,10 +41,11 @@ class _then_receiver : public stdexec::receiver_adaptor<_then_receiver<R, F>, R>
   template <class... As>
     requires stdexec::receiver_of<R, _completions<As...>>
   void set_value(As&&... as) && noexcept {
-    try {
+    STDEXEC_TRY {
       stdexec::set_value(
         std::move(*this).base(), std::invoke(static_cast<F&&>(f_), static_cast<As&&>(as)...));
-    } catch (...) {
+    }
+    STDEXEC_CATCH_ALL {
       stdexec::set_error(std::move(*this).base(), std::current_exception());
     }
   }

examples/benchmark/static_thread_pool_old.hpp

@@ -274,14 +274,15 @@ namespace exec_old {
 
     threads_.reserve(threadCount);
 
-    try {
+    STDEXEC_TRY {
       for (std::uint32_t i = 0; i < threadCount; ++i) {
         threads_.emplace_back([this, i] { run(i); });
       }
-    } catch (...) {
+    }
+    STDEXEC_CATCH_ALL {
       request_stop();
       join();
-      throw;
+      STDEXEC_THROW();
     }
   }
 

examples/hello_coro.cpp

@@ -41,11 +41,12 @@ auto async_stop_token() -> exec::task<std::optional<stdexec::inplace_stop_token>
 }
 
 auto main() -> int {
-  try {
+  STDEXEC_TRY {
     // Awaitables are implicitly senders:
     auto [i] = stdexec::sync_wait(async_answer2(just(42), just())).value();
     std::cout << "The answer is " << i.value() << '\n';
-  } catch (std::exception& e) {
+  }
+  STDEXEC_CATCH(const std::exception& e) {
     std::cout << e.what() << '\n';
   }
 }

examples/server_theme/let_value.cpp

@@ -52,6 +52,7 @@
 // Use a thread pool
 #include "exec/static_thread_pool.hpp"
 
+#if !STDEXEC_STD_NO_EXCEPTIONS()
 namespace ex = stdexec;
 
 struct http_request {
@@ -151,3 +152,11 @@ auto main() -> int {
 
   return 0;
 }
+
+#else
+
+int main() {
+  std::cout << "This example requires C++ exceptions to be enabled.\n";
+  return 0;
+}
+#endif // !STDEXEC_STD_NO_EXCEPTIONS()

include/exec/any_sender_of.hpp

@@ -347,7 +347,7 @@ namespace exec {
           }
           STDEXEC_CATCH_ALL {
             std::allocator_traits<_Alloc>::deallocate(__alloc, __pointer, 1);
-            throw;
+            STDEXEC_THROW();
           }
           __object_pointer_ = __pointer;
         }
@@ -512,7 +512,7 @@ namespace exec {
         }
         STDEXEC_CATCH_ALL {
           std::allocator_traits<_Alloc>::deallocate(__alloc, __pointer, 1);
-          throw;
+          STDEXEC_THROW();
         }
         __object_pointer_ = __pointer;
       }

include/exec/linux/io_uring_context.hpp

@@ -62,7 +62,7 @@ namespace exec {
 
     inline void __throw_error_code_if(bool __cond, int __ec) {
       if (__cond) {
-        throw std::system_error(__ec, std::system_category());
+        STDEXEC_THROW(std::system_error(__ec, std::system_category()));
       }
     }
 
@@ -371,14 +371,15 @@ namespace exec {
 
       void wakeup() {
         if (auto __ec = try_wakeup()) {
-          throw std::system_error{__ec};
+          STDEXEC_THROW(std::system_error{__ec});
         }
       }
 
       /// @brief Resets the io context to its initial state.
       void reset() {
         if (__is_running_.load(std::memory_order_relaxed) || __n_total_submitted_ > 0) {
-          throw std::runtime_error("exec::io_uring_context::reset() called on a running context");
+          STDEXEC_THROW(
+            std::runtime_error("exec::io_uring_context::reset() called on a running context"));
         }
         __n_submissions_in_flight_.store(0, std::memory_order_relaxed);
         __stop_source_.reset();
@@ -474,7 +475,8 @@ namespace exec {
         // Only one thread of execution is allowed to drive the io context.
         if (!__is_running_
                .compare_exchange_strong(expected_running, true, std::memory_order_relaxed)) {
-          throw std::runtime_error("exec::io_uring_context::run() called on a running context");
+          STDEXEC_THROW(
+            std::runtime_error("exec::io_uring_context::run() called on a running context"));
         } else {
           // Check whether we restart the context after a context-wide stop.
           // We have to reset the stop source in this case.

include/exec/static_thread_pool.hpp

@@ -736,7 +736,7 @@ namespace exec {
       STDEXEC_CATCH_ALL {
         request_stop();
         join();
-        throw;
+        STDEXEC_THROW();
       }
     }
 

include/exec/system_context.hpp

@@ -637,7 +637,7 @@ namespace exec {
   inline auto get_parallel_scheduler() -> parallel_scheduler {
     auto __impl = system_context_replaceability::query_parallel_scheduler_backend();
     if (!__impl) {
-      throw std::runtime_error{"No system context implementation found"};
+      STDEXEC_THROW(std::runtime_error{"No system context implementation found"});
     }
     return parallel_scheduler{std::move(__impl)};
   }