From: Ed Schouten <ed@nuxi.nl>
Date: Thu, 11 Aug 2016 20:03:22 +0000 (+0000)
Subject: Don't enable PIE on i686-unknown-cloudabi.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e5174eea266bb5ec9e752f898a42ce3266400fd5;p=clang

Don't enable PIE on i686-unknown-cloudabi.

We're only going to provide support for using PIE on architectures that
provide PC-relative addressing. i686 is not one of those, so add the
necessary bits for only passing in -pie -zrelro conditionally.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@278395 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 175acd8922..fe866dfef3 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -3344,6 +3344,19 @@ Tool *CloudABI::buildLinker() const {
   return new tools::cloudabi::Linker(*this);
 }
 
+bool CloudABI::isPIEDefault() const {
+  // Only enable PIE on architectures that support PC-relative
+  // addressing. PC-relative addressing is required, as the process
+  // startup code must be able to relocate itself.
+  switch (getTriple().getArch()) {
+  case llvm::Triple::aarch64:
+  case llvm::Triple::x86_64:
+    return true;
+  default:
+    return false;
+  }
+}
+
 SanitizerMask CloudABI::getSupportedSanitizers() const {
   SanitizerMask Res = ToolChain::getSupportedSanitizers();
   Res |= SanitizerKind::SafeStack;
diff --git a/lib/Driver/ToolChains.h b/lib/Driver/ToolChains.h
index a80acf7c30..61c559c158 100644
--- a/lib/Driver/ToolChains.h
+++ b/lib/Driver/ToolChains.h
@@ -632,8 +632,7 @@ public:
   void AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
                            llvm::opt::ArgStringList &CmdArgs) const override;
 
-  bool isPIEDefault() const override { return true; }
-
+  bool isPIEDefault() const override;
   SanitizerMask getSupportedSanitizers() const override;
   SanitizerMask getDefaultSanitizers() const override;
 
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 6011a7fa31..0efda4858f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -7523,11 +7523,13 @@ void cloudabi::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
   // CloudABI only supports static linkage.
   CmdArgs.push_back("-Bstatic");
-
-  // CloudABI uses Position Independent Executables exclusively.
-  CmdArgs.push_back("-pie");
   CmdArgs.push_back("--no-dynamic-linker");
-  CmdArgs.push_back("-zrelro");
+
+  // Provide PIE linker flags in case PIE is default for the architecture.
+  if (ToolChain.isPIEDefault()) {
+    CmdArgs.push_back("-pie");
+    CmdArgs.push_back("-zrelro");
+  }
 
   CmdArgs.push_back("--eh-frame-hdr");
   CmdArgs.push_back("--gc-sections");
diff --git a/test/Driver/cloudabi.c b/test/Driver/cloudabi.c
index 7a72f61895..053092a53d 100644
--- a/test/Driver/cloudabi.c
+++ b/test/Driver/cloudabi.c
@@ -1,8 +1,14 @@
 // RUN: %clang %s -### -target x86_64-unknown-cloudabi 2>&1 | FileCheck %s -check-prefix=SAFESTACK
 // SAFESTACK: "-cc1" "-triple" "x86_64-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections" {{.*}} "-fsanitize=safe-stack"
-// SAFESTACK: "-Bstatic" "-pie" "--no-dynamic-linker" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc" "-lcompiler_rt" "crtend.o"
+// SAFESTACK: "-Bstatic" "--no-dynamic-linker" "-pie" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc" "-lcompiler_rt" "crtend.o"
 
 // RUN: %clang %s -### -target x86_64-unknown-cloudabi -fno-sanitize=safe-stack 2>&1 | FileCheck %s -check-prefix=NOSAFESTACK
 // NOSAFESTACK: "-cc1" "-triple" "x86_64-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections"
 // NOSAFESTACK-NOT: "-fsanitize=safe-stack"
-// NOSAFESTACK: "-Bstatic" "-pie" "--no-dynamic-linker" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc" "-lcompiler_rt" "crtend.o"
+// NOSAFESTACK: "-Bstatic" "--no-dynamic-linker" "-pie" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc" "-lcompiler_rt" "crtend.o"
+
+// PIE shouldn't be enabled on i686. Just on architectures that provide
+// PC-relative addressing.
+// RUN: %clang %s -### -target i686-unknown-cloudabi 2>&1 | FileCheck %s -check-prefix=NOPIE
+// NOPIE: "-cc1" "-triple" "i686-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections" {{.*}} "-fsanitize=safe-stack"
+// NOPIE: "-Bstatic" "--no-dynamic-linker" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc" "-lcompiler_rt" "crtend.o"
diff --git a/test/Driver/cloudabi.cpp b/test/Driver/cloudabi.cpp
index dd52ac36ac..f9e9ba5cb4 100644
--- a/test/Driver/cloudabi.cpp
+++ b/test/Driver/cloudabi.cpp
@@ -1,8 +1,14 @@
 // RUN: %clangxx %s -### -target x86_64-unknown-cloudabi 2>&1 | FileCheck %s -check-prefix=SAFESTACK
 // SAFESTACK: "-cc1" "-triple" "x86_64-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections" {{.*}} "-fsanitize=safe-stack"
-// SAFESTACK: "-Bstatic" "-pie" "--no-dynamic-linker" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc++" "-lc++abi" "-lunwind" "-lc" "-lcompiler_rt" "crtend.o"
+// SAFESTACK: "-Bstatic" "--no-dynamic-linker" "-pie" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc++" "-lc++abi" "-lunwind" "-lc" "-lcompiler_rt" "crtend.o"
 
-// RUN: %clangxx %s -### -target x86_64-unknown-cloudabi -fno-sanitize=safe-stack 2>&1 | FileCheck %s -check-prefix=NOSAFESTACk
+// RUN: %clangxx %s -### -target x86_64-unknown-cloudabi -fno-sanitize=safe-stack 2>&1 | FileCheck %s -check-prefix=NOSAFESTACK
 // NOSAFESTACK: "-cc1" "-triple" "x86_64-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections"
 // NOSAFESTACK-NOT: "-fsanitize=safe-stack"
-// NOSAFESTACk: "-Bstatic" "-pie" "--no-dynamic-linker" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc++" "-lc++abi" "-lunwind" "-lc" "-lcompiler_rt" "crtend.o"
+// NOSAFESTACK: "-Bstatic" "--no-dynamic-linker" "-pie" "-zrelro" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc++" "-lc++abi" "-lunwind" "-lc" "-lcompiler_rt" "crtend.o"
+
+// PIE shouldn't be enabled on i686. Just on architectures that provide
+// PC-relative addressing.
+// RUN: %clangxx %s -### -target i686-unknown-cloudabi 2>&1 | FileCheck %s -check-prefix=NOPIE
+// NOPIE: "-cc1" "-triple" "i686-unknown-cloudabi" {{.*}} "-ffunction-sections" "-fdata-sections" {{.*}} "-fsanitize=safe-stack"
+// NOPIE: "-Bstatic" "--no-dynamic-linker" "--eh-frame-hdr" "--gc-sections" "-o" "a.out" "crt0.o" "crtbegin.o" "{{.*}}" "{{.*}}" "-lc++" "-lc++abi" "-lunwind" "-lc" "-lcompiler_rt" "crtend.o"