Backport LLVM patch to fix LLVM build on GCC 11

GCC 11 has changed header dependencies again, so the build of LLVM
fails because <limits> wasn't being included when it should be. This
is already fixed upstream in LLVM 12.

deps/llvm.mk

@@ -484,6 +484,7 @@ $(eval $(call LLVM_PATCH,llvm-julia-tsan-custom-as))
 $(eval $(call LLVM_PATCH,llvm-9.0-D85499)) # landed as D85553
 $(eval $(call LLVM_PATCH,llvm-D80101)) # remove for LLVM 12
 $(eval $(call LLVM_PATCH,llvm-D84031)) # remove for LLVM 12
+$(eval $(call LLVM_PATCH,llvm-rGb498303066a6-gcc11-header-fix)) # remove for LLVM 12
 endif # LLVM_VER 9.0
 
 ifeq ($(LLVM_VER_SHORT),10.0)
@@ -508,6 +509,7 @@ $(eval $(call LLVM_PATCH,llvm-10-unique_function_clang-sa))
 ifeq ($(BUILD_LLVM_CLANG),1)
 $(eval $(call LLVM_PATCH,llvm-D88630-clang-cmake))
 endif
+$(eval $(call LLVM_PATCH,llvm-rGb498303066a6-gcc11-header-fix)) # remove for LLVM 12
 endif # LLVM_VER 10.0
 
 ifeq ($(LLVM_VER_SHORT),11.0)
@@ -535,6 +537,7 @@ $(eval $(call LLVM_PATCH,llvm-11-D93092-ppc-knownbits)) # remove for LLVM 12
 $(eval $(call LLVM_PATCH,llvm-11-D93154-globalisel-as))
 $(eval $(call LLVM_PATCH,llvm-11-ppc-half-ctr)) # remove for LLVM 12
 $(eval $(call LLVM_PATCH,llvm-11-ppc-sp-from-bp)) # remove for LLVM 12
+$(eval $(call LLVM_PATCH,llvm-rGb498303066a6-gcc11-header-fix)) # remove for LLVM 12
 endif # LLVM_VER 11.0
 
 

deps/patches/llvm-rGb498303066a6-gcc11-header-fix.patch

@@ -0,0 +1,21 @@
+From b498303066a63a203d24f739b2d2e0e56dca70d1 Mon Sep 17 00:00:00 2001
+From: serge-sans-paille <sguelton@redhat.com>
+Date: Tue, 10 Nov 2020 14:55:25 +0100
+Subject: [PATCH] [nfc] Fix missing include
+
+---
+ llvm/utils/benchmark/src/benchmark_register.h | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/llvm/utils/benchmark/src/benchmark_register.h b/llvm/utils/benchmark/src/benchmark_register.h
+index 0705e219f2fa..4caa5ad4da07 100644
+--- a/utils/benchmark/src/benchmark_register.h
++++ b/utils/benchmark/src/benchmark_register.h
+@@ -1,6 +1,7 @@
+ #ifndef BENCHMARK_REGISTER_H
+ #define BENCHMARK_REGISTER_H
+
++#include <limits>
+ #include <vector>
+
+ #include "check.h"