[Driver][Fuchsia] Add default linker flags

[mcgrathr]

clang/lib/Driver/ToolChains/Fuchsia.cpp

58

There's a test for lld right below, so you could also just put these in an else block of that.
But I'll leave it to Petr to say which he prefers.

There are only test cases that use -fuse-ld=lld explicitly, which seems odd. It's not so odd that we haven't bothered to test the non-lld behavior before (though ideally we should). But it's a bit odd that we pass it explicitly when it's the default.

[phosek]

LGTM

clang/lib/Driver/ToolChains/Fuchsia.cpp

58

I'd prefer passing these in the else block but either way is fine with me.

[abrachet]

Probably worth looking at this again before I submit

[phosek]

LGTM

[thakis]

This breaks tests on non-linux:

http://45.33.8.238/macm1/45619/step_7.txt
http://45.33.8.238/win/67193/step_7.txt

Please take a look and revert for now if it takes a while to fix.

clang/lib/Driver/ToolChains/Fuchsia.cpp

void fuchsia::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   Args.ClaimAllArgs(options::OPT_w);
 
   CmdArgs.push_back("-z");
   CmdArgs.push_back("max-page-size=4096");
 
   CmdArgs.push_back("-z");
   CmdArgs.push_back("now");
 
   const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
   if (llvm::sys::path::filename(Exec).equals_insensitive("ld.lld") ||
       llvm::sys::path::stem(Exec).equals_insensitive("ld.lld")) {
     CmdArgs.push_back("-z");
     CmdArgs.push_back("rodynamic");
     CmdArgs.push_back("-z");
     CmdArgs.push_back("separate-loadable-segments");
     CmdArgs.push_back("-z");
     CmdArgs.push_back("rel");
     CmdArgs.push_back("--pack-dyn-relocs=relr");
+  } else {
+    // The following are already the default in lld
+    CmdArgs.push_back("-z");
+    CmdArgs.push_back("combreloc");
+    CmdArgs.push_back("-z");
+    CmdArgs.push_back("text");
   }
 
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
   if (!Args.hasArg(options::OPT_shared) && !Args.hasArg(options::OPT_r))
     CmdArgs.push_back("-pie");
 

clang/test/Driver/fuchsia.c

 // RUN: %clang -### %s --target=x86_64-unknown-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
+// RUN: %clang -### %s --target=x86_64-unknown-fuchsia \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
+// RUN: %clang -### %s --target=x86_64-unknown-fuchsia \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform -fuse-ld=gold 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LD,CHECK-X86_64 %s
 // RUN: %clang -### %s --target=aarch64-unknown-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-AARCH64 %s
 // RUN: %clang -### %s --target=riscv64-unknown-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-RISCV64 %s
 // RUN: %clang -### %s --target=x86_64-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
 // RUN: %clang -### %s --target=aarch64-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-AARCH64 %s
 // RUN: %clang -### %s --target=riscv64-fuchsia \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-RISCV64 %s
 // CHECK: "-cc1"
 // CHECK-X86_64: "-triple" "x86_64-unknown-fuchsia"
 // CHECK-AARCH64: "-triple" "aarch64-unknown-fuchsia"
 // CHECK-RISCV64: "-triple" "riscv64-unknown-fuchsia"
 // CHECK: "--mrelax-relocations"
 // CHECK: "-funwind-tables=2"
 // CHECK: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK: "-isysroot" "[[SYSROOT:[^"]+]]"
 // CHECK: "-internal-externc-isystem" "[[SYSROOT]]{{/|\\\\}}include"
 // CHECK-AARCH64: "-fsanitize=shadow-call-stack"
 // CHECK-X86_64: "-fsanitize=safe-stack"
 // CHECK: "-stack-protector" "2"
 // CHECK-AARCH64: "-target-feature" "+outline-atomics"
 // CHECK-NOT: "-fcommon"
-// CHECK: {{.*}}ld.lld{{.*}}" "-z" "max-page-size=4096" "-z" "now" "-z" "rodynamic" "-z" "separate-loadable-segments" "-z" "rel" "--pack-dyn-relocs=relr"
+// CHECK-LLD: {{.*}}ld.lld{{.*}}" "-z" "max-page-size=4096" "-z" "now" "-z" "rodynamic" "-z" "separate-loadable-segments" "-z" "rel" "--pack-dyn-relocs=relr"
+// CHECK-LD: {{.*}}ld.gold{{.*}}" "-z" "max-page-size=4096" "-z" "now" "-z" "combreloc" "-z" "text"
 // CHECK: "--sysroot=[[SYSROOT]]"
 // CHECK: "-pie"
 // CHECK: "--build-id"
 // CHECK: "--hash-style=gnu"
 // CHECK-AARCH64: "--execute-only" "--fix-cortex-a53-843419"
 // CHECK: "-dynamic-linker" "ld.so.1"
 // CHECK-RISCV64: "-X"
 // CHECK: Scrt1.o

clang/test/Driver/fuchsia.cpp

 // RUN: %clangxx -### %s --target=x86_64-unknown-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
+// RUN: %clangxx -### %s --target=x86_64-unknown-fuchsia \
+// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
+// RUN: %clangxx -### %s --target=x86_64-unknown-fuchsia \
+// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     --sysroot=%S/platform -fuse-ld=gold 2>&1 \
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LD,CHECK-X86_64 %s
 // RUN: %clangxx -### %s --target=aarch64-unknown-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-AARCH64 %s
 // RUN: %clangxx -### %s --target=riscv64-unknown-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-RISCV64 %s
 // RUN: %clangxx -### %s --target=x86_64-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-X86_64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-X86_64 %s
 // RUN: %clangxx -### %s --target=aarch64-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-AARCH64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-AARCH64 %s
 // RUN: %clangxx -### %s --target=riscv64-fuchsia \
 // RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     --sysroot=%S/platform -fuse-ld=lld 2>&1 \
-// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-RISCV64 %s
+// RUN:     | FileCheck -check-prefixes=CHECK,CHECK-LLD,CHECK-RISCV64 %s
 // CHECK: "-cc1"
 // CHECK-X86_64: "-triple" "x86_64-unknown-fuchsia"
 // CHECK-AARCH64: "-triple" "aarch64-unknown-fuchsia"
 // CHECK-RISCV64: "-triple" "riscv64-unknown-fuchsia"
 // CHECK-NOT: "-fno-use-init-array"
 // CHECK: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK: "-isysroot" "[[SYSROOT:[^"]+]]"
 // CHECK-X86_64: "-internal-isystem" "{{.*[/\\]}}include{{/|\\\\}}x86_64-unknown-fuchsia{{/|\\\\}}c++{{/|\\\\}}v1"
 // CHECK-AARCH64: "-internal-isystem" "{{.*[/\\]}}include{{/|\\\\}}aarch64-unknown-fuchsia{{/|\\\\}}c++{{/|\\\\}}v1"
 // CHECK-RISCV64: "-internal-isystem" "{{.*[/\\]}}include{{/|\\\\}}riscv64-unknown-fuchsia{{/|\\\\}}c++{{/|\\\\}}v1"
 // CHECK: "-internal-isystem" "{{.*[/\\]}}include{{/|\\\\}}c++{{/|\\\\}}v1"
 // CHECK: "-internal-externc-isystem" "[[SYSROOT]]{{/|\\\\}}include"
-// CHECK: {{.*}}ld.lld{{.*}}" "-z" "now" "-z" "rodynamic" "-z" "separate-loadable-segments"
+// CHECK-LLD: {{.*}}ld.lld{{.*}}" "-z" "max-page-size=4096" "-z" "now" "-z" "rodynamic" "-z" "separate-loadable-segments" "-z" "rel" "--pack-dyn-relocs=relr"
+// CHECK-LD: {{.*}}ld.gold{{.*}}" "-z" "max-page-size=4096" "-z" "now" "-z" "combreloc" "-z" "text"
 // CHECK: "--sysroot=[[SYSROOT]]"
 // CHECK: "-pie"
 // CHECK: "--build-id"
 // CHECK: "-dynamic-linker" "ld.so.1"
 // CHECK: Scrt1.o
 // CHECK-NOT: crti.o
 // CHECK-NOT: crtbegin.o
 // CHECK: "-L[[SYSROOT]]{{/|\\\\}}lib"