From 4b12a3a5a202ddad229f72103b0f04790a1854b7 Mon Sep 17 00:00:00 2001
From: John Brawn <john.brawn@arm.com>
Date: Mon, 10 Aug 2015 11:11:28 +0000
Subject: [PATCH] [Driver] Fix handling of -fbuiltin/-fcommon when combined
 with -mkernel

-mkernel enables -fno-builtin and -fno-common by default, but allows -fbuiltin
and -fcommon to override that. However "-fbuiltin -fno-builtin" is treated the
same as "-fbuiltin" which is wrong, so fix that. Also fixes similar behaviour
when -fno-common is default.

Differential Revision: http://reviews.llvm.org/D11459


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@244437 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Driver/Tools.cpp             | 28 ++++++++++------------------
 test/Driver/apple-kext-mkernel.c | 17 +++++++++++------
 2 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index b82b5f0a07..a04be9cac9 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -4145,7 +4145,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                     options::OPT_fno_lax_vector_conversions))
     CmdArgs.push_back("-fno-lax-vector-conversions");
 
-  if (Args.getLastArg(options::OPT_fapple_kext))
+  if (Args.getLastArg(options::OPT_fapple_kext) ||
+      (Args.hasArg(options::OPT_mkernel) && types::isCXX(InputType)))
     CmdArgs.push_back("-fapple-kext");
 
   Args.AddLastArg(CmdArgs, options::OPT_fobjc_sender_dependent_dispatch);
@@ -4279,15 +4280,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
       A->render(Args, CmdArgs);
   }
 
-  if (Args.hasArg(options::OPT_mkernel)) {
-    if (!Args.hasArg(options::OPT_fapple_kext) && types::isCXX(InputType))
-      CmdArgs.push_back("-fapple-kext");
-    if (!Args.hasArg(options::OPT_fbuiltin))
-      CmdArgs.push_back("-fno-builtin");
-    Args.ClaimAllArgs(options::OPT_fno_builtin);
-  }
-  // -fbuiltin is default.
-  else if (!Args.hasFlag(options::OPT_fbuiltin, options::OPT_fno_builtin))
+  // -fbuiltin is default unless -mkernel is used
+  if (!Args.hasFlag(options::OPT_fbuiltin, options::OPT_fno_builtin,
+                    !Args.hasArg(options::OPT_mkernel)))
     CmdArgs.push_back("-fno-builtin");
 
   if (!Args.hasFlag(options::OPT_fassume_sane_operator_new,
@@ -4687,14 +4682,11 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
-  if (KernelOrKext || isNoCommonDefault(getToolChain().getTriple())) {
-    if (!Args.hasArg(options::OPT_fcommon))
-      CmdArgs.push_back("-fno-common");
-    Args.ClaimAllArgs(options::OPT_fno_common);
-  }
-
-  // -fcommon is default, only pass non-default.
-  else if (!Args.hasFlag(options::OPT_fcommon, options::OPT_fno_common))
+  // -fcommon is the default unless compiling kernel code or the target says so
+  bool NoCommonDefault =
+      KernelOrKext || isNoCommonDefault(getToolChain().getTriple());
+  if (!Args.hasFlag(options::OPT_fcommon, options::OPT_fno_common,
+                    !NoCommonDefault))
     CmdArgs.push_back("-fno-common");
 
   // -fsigned-bitfields is default, and clang doesn't yet support
diff --git a/test/Driver/apple-kext-mkernel.c b/test/Driver/apple-kext-mkernel.c
index 9c20cfce4c..9c60c24e36 100644
--- a/test/Driver/apple-kext-mkernel.c
+++ b/test/Driver/apple-kext-mkernel.c
@@ -1,15 +1,20 @@
-// RUN: %clang -target x86_64-apple-darwin10 \
-// RUN:   -mkernel -### -fsyntax-only %s 2> %t
-// RUN: FileCheck --check-prefix=CHECK-X86 < %t %s
+// RUN: %clang -target x86_64-apple-darwin10 -mkernel -### -fsyntax-only %s 2>&1 | FileCheck --check-prefix=CHECK-X86 %s
+// RUN: %clang -target x86_64-apple-darwin10 -mkernel -### -fsyntax-only -fbuiltin -fno-builtin -fcommon -fno-common %s 2>&1 | FileCheck --check-prefix=CHECK-X86 %s
 
 // CHECK-X86: "-disable-red-zone"
 // CHECK-X86: "-fno-builtin"
 // CHECK-X86: "-fno-rtti"
 // CHECK-X86: "-fno-common"
 
-// RUN: %clang -target x86_64-apple-darwin10 \
-// RUN:   -arch armv7 -mkernel -mstrict-align -### -fsyntax-only %s 2> %t
-// RUN: FileCheck --check-prefix=CHECK-ARM < %t %s
+// RUN: %clang -target x86_64-apple-darwin10 -mkernel -### -fsyntax-only -fbuiltin -fcommon %s 2>&1 | FileCheck --check-prefix=CHECK-X86-2 %s
+
+// CHECK-X86-2: "-disable-red-zone"
+// CHECK-X86-2-NOT: "-fno-builtin"
+// CHECK-X86-2: "-fno-rtti"
+// CHECK-X86-2-NOT: "-fno-common"
+
+// RUN: %clang -target x86_64-apple-darwin10 -arch armv7 -mkernel -mstrict-align -### -fsyntax-only %s 2>&1 | FileCheck --check-prefix=CHECK-ARM %s
+// RUN: %clang -target x86_64-apple-darwin10 -arch armv7 -mkernel -mstrict-align -### -fsyntax-only -fbuiltin -fno-builtin -fcommon -fno-common %s 2>&1 | FileCheck --check-prefix=CHECK-ARM %s
 
 // CHECK-ARM: "-target-feature" "+long-calls"
 // CHECK-ARM: "-target-feature" "+strict-align"
-- 
2.40.0