From 3f624456e6e284f918d4e189e766e357911b49e2 Mon Sep 17 00:00:00 2001
From: Denys Zariaiev <denys.zariaiev@gmail.com>
Date: Tue, 29 Jan 2019 20:54:23 +0100
Subject: [PATCH] Provide PTXLinker with fallback to internal `target-cpu`

---
 src/ci/docker/test-various/Dockerfile         | 2 +-
 src/librustc_codegen_ssa/back/linker.rs       | 6 ++++++
 src/test/run-make/nvptx-binary-crate/Makefile | 7 +++++--
 src/test/run-make/nvptx-dylib-crate/kernel.rs | 2 +-
 4 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/ci/docker/test-various/Dockerfile b/src/ci/docker/test-various/Dockerfile
index a5ae94262c1..6c419e13c9f 100644
--- a/src/ci/docker/test-various/Dockerfile
+++ b/src/ci/docker/test-various/Dockerfile
@@ -14,7 +14,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   xz-utils
 
 # FIXME: build the `ptx-linker` instead.
-RUN curl -sL https://github.com/denzp/rust-ptx-linker/releases/download/v0.9.0-alpha.1/rust-ptx-linker.linux64.tar.gz | \
+RUN curl -sL https://github.com/denzp/rust-ptx-linker/releases/download/v0.9.0-alpha.2/rust-ptx-linker.linux64.tar.gz | \
   tar -xzvC /usr/bin
 
 RUN curl -sL https://nodejs.org/dist/v9.2.0/node-v9.2.0-linux-x64.tar.xz | \
diff --git a/src/librustc_codegen_ssa/back/linker.rs b/src/librustc_codegen_ssa/back/linker.rs
index 55b02ebe6c4..249715a7b6e 100644
--- a/src/librustc_codegen_ssa/back/linker.rs
+++ b/src/librustc_codegen_ssa/back/linker.rs
@@ -1132,6 +1132,12 @@ fn output_filename(&mut self, path: &Path) {
     }
 
     fn finalize(&mut self) -> Command {
+        // Provide the linker with fallback to internal `target-cpu`.
+        self.cmd.arg("--fallback-arch").arg(match self.sess.opts.cg.target_cpu {
+            Some(ref s) => s,
+            None => &self.sess.target.target.options.cpu
+        });
+
         ::std::mem::replace(&mut self.cmd, Command::new(""))
     }
 
diff --git a/src/test/run-make/nvptx-binary-crate/Makefile b/src/test/run-make/nvptx-binary-crate/Makefile
index 4c22dae265c..2c211b5c785 100644
--- a/src/test/run-make/nvptx-binary-crate/Makefile
+++ b/src/test/run-make/nvptx-binary-crate/Makefile
@@ -2,8 +2,11 @@
 
 ifeq ($(TARGET),nvptx64-nvidia-cuda)
 all:
-	$(RUSTC) main.rs -Clink-arg=--arch=sm_60 --crate-type="bin" -O --target $(TARGET)
-	FileCheck main.rs --input-file $(TMPDIR)/main.ptx
+	$(RUSTC) main.rs --crate-type="bin" --target $(TARGET) -O -C link-arg=--arch=sm_60 -o $(TMPDIR)/main.link_arg.ptx
+	$(RUSTC) main.rs --crate-type="bin" --target $(TARGET) -O -C target-cpu=sm_60 -o $(TMPDIR)/main.target_cpu.ptx
+
+	FileCheck main.rs --input-file $(TMPDIR)/main.link_arg.ptx
+	FileCheck main.rs --input-file $(TMPDIR)/main.target_cpu.ptx
 else
 all:
 endif
diff --git a/src/test/run-make/nvptx-dylib-crate/kernel.rs b/src/test/run-make/nvptx-dylib-crate/kernel.rs
index 5e65cca9140..63fd6b063dd 100644
--- a/src/test/run-make/nvptx-dylib-crate/kernel.rs
+++ b/src/test/run-make/nvptx-dylib-crate/kernel.rs
@@ -5,7 +5,7 @@
 extern crate dep;
 
 // Verify the default CUDA arch.
-// CHECK: .target sm_20
+// CHECK: .target sm_30
 // CHECK: .address_size 64
 
 // Make sure declarations are there.
-- 
2.44.0