[Driver] Always use --as-needed with libunwind

With libgcc, we follow the behavior of GCC for backwards compatibility,
only using --as-needed in the non-C++ mode.

With libunwind, there are no backward compatibility requirements so we
can always use --as-needed on all supported platforms.

Differential Revision: https://reviews.llvm.org/D128841

diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index d297b80..2d53b82 100644 (file)
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -1510,7 +1510,8 @@ static void AddUnwindLibrary(const ToolChain &TC, const Driver &D,
     return;
 
   LibGccType LGT = getLibGccType(TC, D, Args);
-  bool AsNeeded = LGT == LibGccType::UnspecifiedLibGcc && !D.CCCIsCXX() &&
+  bool AsNeeded = LGT == LibGccType::UnspecifiedLibGcc &&
+                  (UNW == ToolChain::UNW_CompilerRT || !D.CCCIsCXX()) &&
                   !TC.getTriple().isAndroid() &&
                   !TC.getTriple().isOSCygMing() && !TC.getTriple().isOSAIX();
   if (AsNeeded)

diff --git a/clang/test/Driver/compiler-rt-unwind.c b/clang/test/Driver/compiler-rt-unwind.c
index 85c8db9..c5f63fb 100644 (file)
--- a/clang/test/Driver/compiler-rt-unwind.c
+++ b/clang/test/Driver/compiler-rt-unwind.c
@@ -5,31 +5,48 @@
 // RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=platform \
 // RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-GCC %s
-// RTLIB-GCC: "{{.*}}lgcc"
-// RTLIB-GCC: "{{.*}}lgcc_s"
+// RTLIB-GCC: "-lgcc"
+// RTLIB-GCC-SAME: "--as-needed"
+// RTLIB-GCC-SAME: "-lgcc_s"
+// RTLIB-GCC-SAME: "--no-as-needed"
+//
+// RUN: %clangxx -### %s 2>&1 \
+// RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=platform \
+// RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=RTLIB-GXX %s
+// RTLIB-GXX: "-lgcc"
+// RTLIB-GXX-NOT: "--as-needed"
+// RTLIB-GXX-SAME: "-lgcc_s"
+// RTLIB-GXX-NOT: "--no-as-needed"
 //
 // RUN: %clang -### %s 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=libunwind \
 // RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-GCC-UNWINDLIB-COMPILER-RT %s
-// RTLIB-GCC-UNWINDLIB-COMPILER-RT: "{{.*}}lgcc"
-// RTLIB-GCC-UNWINDLIB-COMPILER-RT: "{{.*}}lunwind"
+// RUN: %clangxx -### %s 2>&1 \
+// RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=libunwind \
+// RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=RTLIB-GCC-UNWINDLIB-COMPILER-RT %s
+// RTLIB-GCC-UNWINDLIB-COMPILER-RT: "-lgcc"
+// RTLIB-GCC-UNWINDLIB-COMPILER-RT-SAME: "--as-needed"
+// RTLIB-GCC-UNWINDLIB-COMPILER-RT-SAME: "-lunwind"
+// RTLIB-GCC-UNWINDLIB-COMPILER-RT-SAME: "--no-as-needed"
 //
 // RUN: %clang -### %s 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=libunwind \
 // RUN:     -shared-libgcc \
 // RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-GCC-SHARED-UNWINDLIB-COMPILER-RT %s
-// RTLIB-GCC-SHARED-UNWINDLIB-COMPILER-RT: "{{.*}}l:libunwind.so"
-// RTLIB-GCC-SHARED-UNWINDLIB-COMPILER-RT: "{{.*}}lgcc"
+// RTLIB-GCC-SHARED-UNWINDLIB-COMPILER-RT: "-l:libunwind.so"
+// RTLIB-GCC-SHARED-UNWINDLIB-COMPILER-RT-SAME: "-lgcc"
 //
 // RUN: %clang -### %s 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=libunwind \
 // RUN:     -static-libgcc \
 // RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-GCC-STATIC-UNWINDLIB-COMPILER-RT %s
-// RTLIB-GCC-STATIC-UNWINDLIB-COMPILER-RT: "{{.*}}lgcc"
-// RTLIB-GCC-STATIC-UNWINDLIB-COMPILER-RT: "{{.*}}l:libunwind.a"
+// RTLIB-GCC-STATIC-UNWINDLIB-COMPILER-RT: "-lgcc"
+// RTLIB-GCC-STATIC-UNWINDLIB-COMPILER-RT-SAME: "-l:libunwind.a"
 //
 // RUN: %clang -### %s 2>&1   \
 // RUN:     --target=x86_64-unknown-linux -rtlib=compiler-rt \
@@ -37,19 +54,32 @@
 // RUN:   | FileCheck --check-prefix=RTLIB-COMPILER-RT %s
 // RTLIB-COMPILER-RT: "{{.*}}libclang_rt.builtins-x86_64.a"
 //
+// RUN: %clang -### %s 2>&1 \
+// RUN:     --target=x86_64-unknown-linux -rtlib=compiler-rt --unwindlib=libunwind \
+// RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT %s
+// RUN: %clangxx -### %s 2>&1 \
+// RUN:     --target=x86_64-unknown-linux -rtlib=compiler-rt --unwindlib=libunwind \
+// RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
+// RUN:   | FileCheck --check-prefix=RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT %s
+// RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT: "{{.*}}libclang_rt.builtins-x86_64.a"
+// RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT-SAME: "--as-needed"
+// RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT-SAME: "-lunwind"
+// RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT-SAME: "--no-as-needed"
+//
 // RUN: %clang -### %s 2>&1   \
 // RUN:     --target=x86_64-unknown-linux -rtlib=compiler-rt --unwindlib=libgcc \
 // RUN:     --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-COMPILER-RT-UNWINDLIB-GCC %s
 // RTLIB-COMPILER-RT-UNWINDLIB-GCC: "{{.*}}libclang_rt.builtins-x86_64.a"
-// RTLIB-COMPILER-RT-UNWINDLIB-GCC: "{{.*}}lgcc_s"
+// RTLIB-COMPILER-RT-UNWINDLIB-GCC-SAME: "-lgcc_s"
 //
 // RUN: %clang -### %s 2>&1              \
 // RUN:     --target=x86_64-unknown-linux -rtlib=compiler-rt --unwindlib=libgcc \
 // RUN:     -static --gcc-toolchain="" -resource-dir=%S/Inputs/resource_dir \
 // RUN:   | FileCheck --check-prefix=RTLIB-COMPILER-RT-UNWINDLIB-GCC-STATIC %s
 // RTLIB-COMPILER-RT-UNWINDLIB-GCC-STATIC: "{{.*}}libclang_rt.builtins-x86_64.a"
-// RTLIB-COMPILER-RT-UNWINDLIB-GCC-STATIC: "{{.*}}lgcc_eh"
+// RTLIB-COMPILER-RT-UNWINDLIB-GCC-STATIC-SAME: "-lgcc_eh"
 //
 // RUN: not %clang %s 2> %t.err              \
 // RUN:     --target=x86_64-unknown-linux -rtlib=libgcc --unwindlib=libunwind \
@@ -63,7 +93,7 @@
 // RUN:     --gcc-toolchain="" \
 // RUN:   | FileCheck --check-prefix=MINGW-RTLIB-COMPILER-RT-SHARED-UNWINDLIB-COMPILER-RT %s
 // MINGW-RTLIB-COMPILER-RT-SHARED-UNWINDLIB-COMPILER-RT: "{{.*}}libclang_rt.builtins-x86_64.a"
-// MINGW-RTLIB-COMPILER-RT-SHARED-UNWINDLIB-COMPILER-RT: "{{.*}}l:libunwind.dll.a"
+// MINGW-RTLIB-COMPILER-RT-SHARED-UNWINDLIB-COMPILER-RT-SAME: "-l:libunwind.dll.a"
 //
 // RUN: %clang -### %s 2>&1 \
 // RUN:     --target=x86_64-w64-mingw32 -rtlib=compiler-rt --unwindlib=libunwind \
@@ -71,7 +101,7 @@
 // RUN:     --gcc-toolchain="" \
 // RUN:   | FileCheck --check-prefix=MINGW-RTLIB-COMPILER-RT-STATIC-UNWINDLIB-COMPILER-RT %s
 // MINGW-RTLIB-COMPILER-RT-STATIC-UNWINDLIB-COMPILER-RT: "{{.*}}libclang_rt.builtins-x86_64.a"
-// MINGW-RTLIB-COMPILER-RT-STATIC-UNWINDLIB-COMPILER-RT: "{{.*}}l:libunwind.a"
+// MINGW-RTLIB-COMPILER-RT-STATIC-UNWINDLIB-COMPILER-RT-SAME: "-l:libunwind.a"
 //
 // RUN: %clang -### %s 2>&1 \
 // RUN:     --target=x86_64-w64-mingw32 -rtlib=compiler-rt --unwindlib=libunwind \
@@ -82,4 +112,4 @@
 // RUN:     --gcc-toolchain="" \
 // RUN:   | FileCheck --check-prefix=MINGW-RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT %s
 // MINGW-RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT: "{{.*}}libclang_rt.builtins-x86_64.a"
-// MINGW-RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT: "{{.*}}lunwind"
+// MINGW-RTLIB-COMPILER-RT-UNWINDLIB-COMPILER-RT-SAME: "-lunwind"