[clang] Make test for linking libc++ on Darwin more portable

Specify the path to the linker explicitly so that we can run the
test on all platforms regardless of what linker is being used.

Author: ldionne

clang/test/Driver/darwin-link-libcxx.cpp

@@ -1,33 +1,36 @@
 // UNSUPPORTED: system-windows
 
-// TODO: Make this test portable across platforms
-// REQUIRES: system-darwin
-
 // Tests to check that we link against the toolchain-provided libc++ built library when it is provided.
 // This is required to prefer the toolchain's libc++ over the system's libc++, which matches the behavior
 // we have for header search paths.
+//
+// Note that we explicitly specify the linker path to use to make this test portable across platforms.
 
 // When libc++.dylib is NOT in the toolchain, we should use -lc++ and fall back to the libc++
 // in the sysroot.
 //
 // (1) Without -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_no_libcxx/usr/bin \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_no_libcxx    \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-1 %s
-// CHECK-1: "/usr/bin/ld"
+// CHECK-1: "[[INPUTS]]/lld/ld.lld"
 // CHECK-1: "-lc++"
 // CHECK-1-NOT: "[[TOOLCHAIN]]/usr/lib"
 //
 // (2) With -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_no_libcxx/usr/bin \
 // RUN:     -fexperimental-library                                              \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_no_libcxx    \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-2 %s
-// CHECK-2: "/usr/bin/ld"
+// CHECK-2: "[[INPUTS]]/lld/ld.lld"
 // CHECK-2: "-lc++" "-lc++experimental"
 // CHECK-2-NOT: "[[TOOLCHAIN]]/usr/lib"
 
@@ -37,21 +40,25 @@
 // (1) Without -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin           \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain              \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-3 %s
-// CHECK-3: "/usr/bin/ld"
+// CHECK-3: "[[INPUTS]]/lld/ld.lld"
 // CHECK-3: "[[TOOLCHAIN]]/usr/lib/libc++.dylib"
 // CHECK-3-NOT: "-lc++"
 //
 // (2) With -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain/usr/bin           \
 // RUN:     -fexperimental-library                                              \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain              \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-4 %s
-// CHECK-4: "/usr/bin/ld"
+// CHECK-4: "[[INPUTS]]/lld/ld.lld"
 // CHECK-4: "[[TOOLCHAIN]]/usr/lib/libc++.dylib"
 // CHECK-4: "[[TOOLCHAIN]]/usr/lib/libc++experimental.a"
 // CHECK-4-NOT: "-lc++"
@@ -63,21 +70,25 @@
 // (1) Without -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_static/usr/bin    \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_static       \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-5 %s
-// CHECK-5: "/usr/bin/ld"
+// CHECK-5: "[[INPUTS]]/lld/ld.lld"
 // CHECK-5: "[[TOOLCHAIN]]/usr/lib/libc++.a"
 // CHECK-5-NOT: "-lc++"
 //
 // (2) With -fexperimental-library.
 // RUN: %clangxx -### %s 2>&1                                                   \
 // RUN:     --target=x86_64-apple-darwin                                        \
+// RUN:     --ld-path=%S/Inputs/lld/ld.lld                                      \
 // RUN:     -ccc-install-dir %S/Inputs/basic_darwin_toolchain_static/usr/bin    \
 // RUN:     -fexperimental-library                                              \
 // RUN:   | FileCheck -DTOOLCHAIN=%S/Inputs/basic_darwin_toolchain_static       \
+// RUN:               -DINPUTS=%S/Inputs                                        \
 // RUN:               --check-prefix=CHECK-6 %s
-// CHECK-6: "/usr/bin/ld"
+// CHECK-6: "[[INPUTS]]/lld/ld.lld"
 // CHECK-6: "[[TOOLCHAIN]]/usr/lib/libc++.a"
 // CHECK-6: "[[TOOLCHAIN]]/usr/lib/libc++experimental.a"
 // CHECK-6-NOT: "-lc++"