From: Natanael Copa <ncopa@alpinelinux.org>
From: Jakub Jirutka <jakub@jirutka.cz>
Date: Sun, 16 Apr 2017 16:49:00 +0100
Subject: [PATCH] Enable PIE by default for Alpine Linux

Alpine Linux uses PIE by default.

--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -4721,7 +4721,10 @@
   }
 }
 
-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;
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -9258,7 +9258,9 @@
   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");
 
   CmdArgs.push_back("--eh-frame-hdr");
--- a/test/Driver/pic.c
+++ b/test/Driver/pic.c
@@ -244,6 +244,18 @@
 // 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