From 2d8601701dc97527d723e91a05272624063e0c51 Mon Sep 17 00:00:00 2001
From: Riatre Foo <foo@riat.re>
Date: Fri, 3 Jul 2020 00:07:43 +0800
Subject: [PATCH] Fix build action order

Add $(INCTARGETS) to build dependencies of %.o and $(DEVICELIB).
As there were no dep files during the first build, Make may kick off source
compilation before nccl.h got generated, which leads to occasional build
failures on systems with high core count. The build failure could be
reproduced reliably with a `sleep 5` in $(INCDIR)/nccl.h rule.
---
 src/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Makefile b/src/Makefile
index d065888..487f790 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -46,7 +46,7 @@ lib : $(INCTARGETS) $(LIBDIR)/$(LIBTARGET) $(PKGDIR)/$(PKGTARGET)
 
 staticlib : $(LIBDIR)/$(STATICLIBTARGET)
 
-$(DEVICELIB): ALWAYS_REBUILD
+$(DEVICELIB): ALWAYS_REBUILD $(INCTARGETS)
 	$(MAKE) -C collectives/device
 
 # Empty target to force rebuild
@@ -107,7 +107,7 @@ $(PKGDIR)/%.pc : %.pc
 	mkdir -p $(PKGDIR)
 	install -m 644 $< $@
 
-$(OBJDIR)/%.o : %.cc
+$(OBJDIR)/%.o : %.cc $(INCTARGETS)
 	@printf "Compiling  %-35s > %s\n" $< $@
 	mkdir -p `dirname $@`
 	$(CXX) -I. -I$(INCDIR) $(CXXFLAGS) -Iinclude -c $< -o $@