From efbdf70c883a356106fc1bcb1c2917ec6c0a6157 Mon Sep 17 00:00:00 2001
From: Natanael Copa <ncopa@alpinelinux.org>
Date: Tue, 23 Feb 2016 09:35:26 +0100
Subject: [PATCH 5/7] Enable PIE by default for alpine linux

Alpine Linux uses PIE by default.
---
 lib/Driver/ToolChains.cpp |  5 ++++-
 lib/Driver/Tools.cpp      |  4 +++-
 test/Driver/pic.c         | 12 ++++++++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 0db9644..82449bf 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -4143,7 +4143,10 @@ void Linux::AddCudaIncludeArgs(const ArgList &DriverArgs,
   }
 }
 
-bool Linux::isPIEDefault() const { return getSanitizerArgs().requiresPIE(); }
+bool Linux::isPIEDefault() const {
+  return getSanitizerArgs().requiresPIE() ||
+         Linux::getTriple().getVendorName().compare("alpine") == 0;
+}
 
 SanitizerMask Linux::getSupportedSanitizers() const {
   const bool IsX86 = getTriple().getArch() == llvm::Triple::x86;
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index ea1ce6f..8fd3649 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -7919,7 +7919,9 @@ void freebsd::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
-  if (IsPIE)
+  if (Args.hasArg(options::OPT_nopie))
+    CmdArgs.push_back("-nopie");
+  else if (IsPIE)
     CmdArgs.push_back("-pie");
 
   if (Args.hasArg(options::OPT_static)) {
diff --git a/test/Driver/pic.c b/test/Driver/pic.c
index aeb2ee3..9b8e0f6 100644
--- a/test/Driver/pic.c
+++ b/test/Driver/pic.c
@@ -243,6 +243,18 @@
 // RUN: %clang %s -target i386-pc-openbsd -nopie -### 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=CHECK-NOPIE-LD
 //
+// On Alpine Linux, we want similar PIE-by-default behavior
+// RUN: %clang -c %s -target x86_64-alpine-linux-musl -### 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-PIE2
+// RUN: %clang -c %s -target i686-alpine-linux-musl -### 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-PIE2
+// RUN: %clang -c %s -target armv6-alpine-linux-musleabihf -### 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-PIE2
+// RUN: %clang -c %s -target armv7-alpine-linux-musleabihf -### 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-PIE2
+// RUN: %clang %s -target x86_64-alpine-linux-musl -nopie -### 2>&1 \
+// RUN:   | FileCheck %s --check-prefix=CHECK-NOPIE-LD
+//
 // On Android PIC is enabled by default
 // RUN: %clang -c %s -target i686-linux-android -### 2>&1 \
 // RUN:   | FileCheck %s --check-prefix=CHECK-PIC2
-- 
2.7.3