rust: add patch to limit internalization

without this patch, some packages fail to build on i686

[ci skip]

srcpkgs/rust/patches/limit-internalization.patch

@@ -0,0 +1,27 @@
+From b4131e297e18fde119f6f461b3e622218166b009 Mon Sep 17 00:00:00 2001
+From: Josh Stone <jistone@redhat.com>
+Date: Fri, 26 Apr 2019 08:58:14 -0700
+Subject: [PATCH] Limit internalization in LLVM 8 ThinLTO
+
+---
+ src/rustllvm/PassWrapper.cpp | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
+index 319c66a21f17..0ebef82d3768 100644
+--- a/src/rustllvm/PassWrapper.cpp
++++ b/src/rustllvm/PassWrapper.cpp
+@@ -873,8 +873,11 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
+     return PrevailingType::Unknown;
+   };
+ #if LLVM_VERSION_GE(8, 0)
++  // We don't have a complete picture in our use of ThinLTO, just our immediate
++  // crate, so we need `ImportEnabled = false` to limit internalization.
++  // Otherwise, we sometimes lose `static` values -- see #60184.
+   computeDeadSymbolsWithConstProp(Ret->Index, Ret->GUIDPreservedSymbols,
+-                                  deadIsPrevailing, /* ImportEnabled = */ true);
++                                  deadIsPrevailing, /* ImportEnabled = */ false);
+ #else
+   computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols, deadIsPrevailing);
+ #endif
+

srcpkgs/rust/template

@@ -1,7 +1,7 @@
 # Template file for 'rust'
 pkgname=rust
 version=1.35.0
-revision=1
+revision=2
 _rust_dist_version=1.35.0
 _cargo_dist_version=0.36.0
 # Always make sure custom distfiles used for bootstrap are