[Driver][Fuchsia] Support -nolibc flag

This can be used to disable libc linking. This flag is supported by
GCC since version 9 as well as some Clang target toolchains. This
change also includes tests for all -no* flags which previously weren't
covered.

Differential Revision: https://reviews.llvm.org/D58325

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@354208 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/ToolChains/Fuchsia.cpp b/lib/Driver/ToolChains/Fuchsia.cpp
index 1ca52eb62bdaa284630cad636b9388763e24584e..0db6d0e15993b0ccec9673295914deea49d08b60 100644 (file)
--- a/lib/Driver/ToolChains/Fuchsia.cpp
+++ b/lib/Driver/ToolChains/Fuchsia.cpp
@@ -148,7 +148,8 @@ void fuchsia::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     if (Args.hasArg(options::OPT_fsplit_stack))
       CmdArgs.push_back("--wrap=pthread_create");
 
-    CmdArgs.push_back("-lc");
+    if (!Args.hasArg(options::OPT_nolibc))
+      CmdArgs.push_back("-lc");
   }
 
   C.addCommand(llvm::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));

diff --git a/test/Driver/fuchsia.c b/test/Driver/fuchsia.c
index 9c3ea53009bc306b489b8930d9c826f95d650074..a01265494663679a817fd46dacbc2096ee3f00bd 100644 (file)
--- a/test/Driver/fuchsia.c
+++ b/test/Driver/fuchsia.c
@@ -53,6 +53,27 @@
 // CHECK-RELOCATABLE-NOT: "--build-id"
 // CHECK-RELOCATABLE: "-r"
 
+// RUN: %clang %s -### --target=x86_64-fuchsia -nodefaultlibs -fuse-ld=lld 2>&1 \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     | FileCheck %s -check-prefix=CHECK-NODEFAULTLIBS
+// CHECK-NODEFAULTLIBS: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+// CHECK-NODEFAULTLIBS-NOT: "[[RESOURCE_DIR]]{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}lib{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-NODEFAULTLIBS-NOT: "-lc"
+
+// RUN: %clang %s -### --target=x86_64-fuchsia -nostdlib -fuse-ld=lld 2>&1 \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     | FileCheck %s -check-prefix=CHECK-NOSTDLIB
+// CHECK-NOSTDLIB: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+// CHECK-NOSTDLIB-NOT: "[[RESOURCE_DIR]]{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}lib{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-NOSTDLIB-NOT: "-lc"
+
+// RUN: %clang %s -### --target=x86_64-fuchsia -nolibc -fuse-ld=lld 2>&1 \
+// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
+// RUN:     | FileCheck %s -check-prefix=CHECK-NOLIBC
+// CHECK-NOLIBC: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
+// CHECK-NOLIBC: "[[RESOURCE_DIR]]{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}lib{{/|\\\\}}libclang_rt.builtins.a"
+// CHECK-NOLIBC-NOT: "-lc"
+
 // RUN: %clang %s -### --target=x86_64-fuchsia \
 // RUN:     -fsanitize=safe-stack 2>&1 \
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \

diff --git a/test/Driver/fuchsia.cpp b/test/Driver/fuchsia.cpp
index 2c80ad070378c47445461c8bd0e491cdd54ff15a..d18d496359f66fa974b62e5ec344a2e7ff8a5a68 100644 (file)
--- a/test/Driver/fuchsia.cpp
+++ b/test/Driver/fuchsia.cpp
@@ -43,3 +43,9 @@
 // CHECK-STATIC: "-lm"
 // CHECK-STATIC: "--pop-state"
 // CHECK-STATIC: "-lc"
+
+// RUN: %clang %s -### --target=x86_64-fuchsia -nostdlib++ -fuse-ld=lld 2>&1 \
+// RUN:     | FileCheck %s -check-prefix=CHECK-NOSTDLIBXX
+// CHECK-NOSTDLIBXX-NOT: "-lc++"
+// CHECK-NOSTDLIBXX-NOT: "-lm"
+// CHECK-NOSTDLIBXX: "-lc"