From 69f87e5418ea81e829a625fcc7de20c8d79d257e Mon Sep 17 00:00:00 2001
From: Rene Rivera <grafikrobot@gmail.com>
Date: Tue, 29 Aug 2023 20:03:31 -0500
Subject: [PATCH] Fix min parallelism when threads fail to run.

---
 src/engine/tasks.cpp | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/engine/tasks.cpp b/src/engine/tasks.cpp
index f9b4db61f5..72e32fc3e1 100644
--- a/src/engine/tasks.cpp
+++ b/src/engine/tasks.cpp
@@ -222,8 +222,15 @@ inline executor::implementation::implementation(unsigned parallelism)
 	runners.reserve(parallelism);
 	for (; parallelism > 0; --parallelism)
 	{
-		running_count += 1;
-		runners.emplace_back([this]() { runner(); });
+		try
+		{
+			runners.emplace_back([this]() { runner(); });
+			running_count += 1;
+		}
+		catch (const std::system_error & e)
+		{
+			err_printf("Task execution error: %s");
+		}
 	}
 #endif
 }
@@ -348,7 +355,8 @@ executor::~executor() { i->stop(); }
 
 std::shared_ptr<group> executor::make(int parallelism)
 {
-	auto result = std::make_shared<group>(*this, get_parallelism(parallelism));
+	auto result = std::make_shared<group>(*this,
+		std::min(unsigned(i->runners.size()), get_parallelism(parallelism)));
 	i->push_group(result);
 	return result;
 }