From 2b944146ee1b48be08e2cb0d23b664469471721d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ricardo=20Lu=C3=ADs=20Vaz=20Silva?= <ricolvs123@gmail.com>
Date: Sat, 23 Sep 2023 16:28:35 -0300
Subject: [PATCH] disable r_particles_multithreaded on platforms missing
 library support

---
 src/playsim/p_effect.cpp | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/playsim/p_effect.cpp b/src/playsim/p_effect.cpp
index 0fd25f12389..ff99c7aa60f 100644
--- a/src/playsim/p_effect.cpp
+++ b/src/playsim/p_effect.cpp
@@ -34,7 +34,11 @@
 ** more useful.
 */
 
-#include <execution>
+#if __has_include(<execution>)
+
+	#include <execution>
+
+#endif
 
 #include "doomtype.h"
 #include "doomstat.h"
@@ -58,7 +62,12 @@ CVAR (Bool, r_rail_smartspiral, false, CVAR_ARCHIVE);
 CVAR (Int, r_rail_spiralsparsity, 1, CVAR_ARCHIVE);
 CVAR (Int, r_rail_trailsparsity, 1, CVAR_ARCHIVE);
 CVAR (Bool, r_particles, true, 0);
-CVAR (Bool, r_particles_multithreaded, true, CVAR_ARCHIVE);
+
+#if __has_include(<execution>)
+
+	CVAR (Bool, r_particles_multithreaded, true, CVAR_ARCHIVE);
+
+#endif
 EXTERN_CVAR(Int, r_maxparticles);
 
 FRandom pr_railtrail("RailTrail");
@@ -280,6 +289,7 @@ void P_ThinkParticles (FLevelLocals *Level)
 {
 	uint64_t startNs = I_nsTime();
 	std::deque<particle_t>::iterator newEnd;
+#if __has_include(<execution>)
 	if(r_particles_multithreaded)
 	{
 		newEnd = std::remove_if(std::execution::par_unseq, Level->Particles.begin(), Level->Particles.end(), [Level](particle_t &p)
@@ -288,6 +298,7 @@ void P_ThinkParticles (FLevelLocals *Level)
 		});
 	}
 	else
+#endif
 	{
 		newEnd = std::remove_if(Level->Particles.begin(), Level->Particles.end(), [Level](particle_t &p)
 		{