[clang] [llvm] [DTLTO][Clang] Add support for Integrated Distributed ThinLTO (PR #147265)

[via llvm-commits]

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+// REQUIRES: lld
+
+/// Check DTLTO options are forwarded to the linker.
+
+// RUN: echo "--target=x86_64-linux-gnu \
+// RUN:   -Xthinlto-distributor=distarg1 \
+// RUN:   -Xthinlto-distributor=distarg2,distarg3 \
+// RUN:   -fuse-ld=lld" > %t.rsp
+
+/// Check that options are forwarded as expected with --thinlto-distributor=.
+// RUN: %clang -### @%t.rsp -fthinlto-distributor=dist.exe %s 2>&1 | \
+// RUN:   FileCheck %s --implicit-check-not=warning
+
+// CHECK: ld.lld
+// CHECK-SAME: "--thinlto-distributor=dist.exe"
+// CHECK-SAME: "--thinlto-remote-compiler={{.*}}clang
+// CHECK-SAME: "--thinlto-distributor-arg=distarg1"
+// CHECK-SAME: "--thinlto-distributor-arg=distarg2"
+// CHECK-SAME: "--thinlto-distributor-arg=distarg3"
+
+
+/// Check that options are not added without --thinlto-distributor= and
+/// that there is an unused option warning issued for -Xthinlto-distributor=
+/// options. We specify -flto here as these options should be unaffected by it.
+// RUN: %clang -### @%t.rsp -flto=thin %s 2>&1 | \
+// RUN:   FileCheck %s --check-prefixes=NONE,NOMORE --implicit-check-not=warning
+
+// NONE: warning: argument unused during compilation: '-Xthinlto-distributor=distarg1'
+// NONE: warning: argument unused during compilation: '-Xthinlto-distributor=distarg2,distarg3'
+// NONE:     ld.lld
+// NOMORE-NOT: distributor
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bd1976bris wrote:

@teresajohnson I have now removed the use of response files and implemented (judiciously) @MaskRay's suggestion of using `-Werror`.

https://github.com/llvm/llvm-project/pull/147265