Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain #147589

quic-garvgupt · 2025-07-08T19:47:26Z

No description provided.

llvmbot · 2025-07-08T19:47:57Z

@llvm/pr-subscribers-backend-risc-v

@llvm/pr-subscribers-clang

Author: Garvit Gupta (quic-garvgupt)

Changes

Full diff: https://github.com/llvm/llvm-project/pull/147589.diff

9 Files Affected:

(modified) clang/include/clang/Driver/CommonArgs.h (+2)
(modified) clang/lib/Driver/ToolChains/BareMetal.cpp (+15-4)
(modified) clang/lib/Driver/ToolChains/CommonArgs.cpp (+12)
(modified) clang/lib/Driver/ToolChains/Gnu.cpp (-12)
(modified) clang/test/Driver/aarch64-toolchain.c (+12)
(modified) clang/test/Driver/arm-toolchain.c (+12)
(modified) clang/test/Driver/baremetal.cpp (+26)
(modified) clang/test/Driver/riscv32-toolchain.c (+13)
(modified) clang/test/Driver/riscv64-toolchain.c (+13)

diff --git a/clang/include/clang/Driver/CommonArgs.h b/clang/include/clang/Driver/CommonArgs.h
index 26aa3ccf84786..d8877903c892f 100644
--- a/clang/include/clang/Driver/CommonArgs.h
+++ b/clang/include/clang/Driver/CommonArgs.h
@@ -85,6 +85,8 @@ const char *RelocationModelName(llvm::Reloc::Model Model);
 std::tuple<llvm::Reloc::Model, unsigned, bool>
 ParsePICArgs(const ToolChain &ToolChain, const llvm::opt::ArgList &Args);
 
+bool getStaticPIE(const llvm::opt::ArgList &Args, const ToolChain &TC);
+
 unsigned ParseFunctionAlignment(const ToolChain &TC,
                                 const llvm::opt::ArgList &Args);
 
diff --git a/clang/lib/Driver/ToolChains/BareMetal.cpp b/clang/lib/Driver/ToolChains/BareMetal.cpp
index e670696cd59ae..6ee3fbe400566 100644
--- a/clang/lib/Driver/ToolChains/BareMetal.cpp
+++ b/clang/lib/Driver/ToolChains/BareMetal.cpp
@@ -599,11 +599,18 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   const Driver &D = getToolChain().getDriver();
   const llvm::Triple::ArchType Arch = TC.getArch();
   const llvm::Triple &Triple = getToolChain().getEffectiveTriple();
+  const bool IsStaticPIE = getStaticPIE(Args, TC);
 
   if (!D.SysRoot.empty())
     CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
 
   CmdArgs.push_back("-Bstatic");
+  if(IsStaticPIE) {
+    CmdArgs.push_back("-pie");
+    CmdArgs.push_back("--no-dynamic-linker");
+    CmdArgs.push_back("-z");
+    CmdArgs.push_back("text");
+  }
 
   if (const char *LDMOption = getLDMOption(TC.getTriple(), Args)) {
     CmdArgs.push_back("-m");
@@ -633,14 +640,18 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
   const char *CRTBegin, *CRTEnd;
   if (NeedCRTs) {
-    if (!Args.hasArg(options::OPT_r))
-      CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath("crt0.o")));
+    if (!Args.hasArg(options::OPT_r)) {
+      const char *crt = "crt0.o";
+      if (IsStaticPIE)
+        crt = "rcrt1.o";
+      CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath(crt)));
+    }
     if (TC.hasValidGCCInstallation() || detectGCCToolchainAdjacent(D)) {
       auto RuntimeLib = TC.GetRuntimeLibType(Args);
       switch (RuntimeLib) {
       case (ToolChain::RLT_Libgcc): {
-        CRTBegin = "crtbegin.o";
-        CRTEnd = "crtend.o";
+        CRTBegin = IsStaticPIE ? "crtbeginS.o" : "crtbegin.o";
+        CRTEnd = IsStaticPIE ? "crtendS.o" : "crtend.o";
         break;
       }
       case (ToolChain::RLT_CompilerRT): {
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index bdd77ac84913c..f8f97b02a5f95 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -2089,6 +2089,18 @@ tools::ParsePICArgs(const ToolChain &ToolChain, const ArgList &Args) {
   return std::make_tuple(RelocM, 0U, false);
 }
 
+bool tools::getStaticPIE(const ArgList &Args, const ToolChain &TC) {
+  bool HasStaticPIE = Args.hasArg(options::OPT_static_pie);
+  if (HasStaticPIE && Args.hasArg(options::OPT_no_pie)) {
+    const Driver &D = TC.getDriver();
+    const llvm::opt::OptTable &Opts = D.getOpts();
+    StringRef StaticPIEName = Opts.getOptionName(options::OPT_static_pie);
+    StringRef NoPIEName = Opts.getOptionName(options::OPT_nopie);
+    D.Diag(diag::err_drv_cannot_mix_options) << StaticPIEName << NoPIEName;
+  }
+  return HasStaticPIE;
+}
+
 // `-falign-functions` indicates that the functions should be aligned to the
 // backend's preferred alignment.
 //
diff --git a/clang/lib/Driver/ToolChains/Gnu.cpp b/clang/lib/Driver/ToolChains/Gnu.cpp
index f5e2655857432..01b146db24f3e 100644
--- a/clang/lib/Driver/ToolChains/Gnu.cpp
+++ b/clang/lib/Driver/ToolChains/Gnu.cpp
@@ -219,18 +219,6 @@ void tools::gcc::Linker::RenderExtraToolArgs(const JobAction &JA,
   // The types are (hopefully) good enough.
 }
 
-static bool getStaticPIE(const ArgList &Args, const ToolChain &TC) {
-  bool HasStaticPIE = Args.hasArg(options::OPT_static_pie);
-  if (HasStaticPIE && Args.hasArg(options::OPT_no_pie)) {
-    const Driver &D = TC.getDriver();
-    const llvm::opt::OptTable &Opts = D.getOpts();
-    StringRef StaticPIEName = Opts.getOptionName(options::OPT_static_pie);
-    StringRef NoPIEName = Opts.getOptionName(options::OPT_nopie);
-    D.Diag(diag::err_drv_cannot_mix_options) << StaticPIEName << NoPIEName;
-  }
-  return HasStaticPIE;
-}
-
 static bool getStatic(const ArgList &Args) {
   return Args.hasArg(options::OPT_static) &&
       !Args.hasArg(options::OPT_static_pie);
diff --git a/clang/test/Driver/aarch64-toolchain.c b/clang/test/Driver/aarch64-toolchain.c
index cfad4b8eb6829..4dc970f0e8685 100644
--- a/clang/test/Driver/aarch64-toolchain.c
+++ b/clang/test/Driver/aarch64-toolchain.c
@@ -157,3 +157,15 @@
 // AARCH64-BAREMETAL-UNWINDLIB: "{{.*}}clang_rt.crtbegin.o"
 // AARCH64-BAREMETAL-UNWINDLIB: "--start-group" "{{.*}}libclang_rt.builtins{{.*}}.a" "--as-needed" "-lunwind" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // AARCH64-BAREMETAL-UNWINDLIB: "{{.*}}clang_rt.crtend.o"
+
+// RUN: %clang -static-pie -### %s -fuse-ld= \
+// RUN:   --target=aarch64-none-elf --rtlib=libgcc --unwindlib=platform \
+// RUN:   --gcc-toolchain=%S/Inputs/basic_aarch64_gcc_tree \
+// RUN:   --sysroot=%S/Inputs/basic_arm_gcc_tree/aarch64-none-elf 2>&1 \
+// RUN:   | FileCheck -check-prefix=C-ARM-STATIC-PIE %s
+
+// C-ARM-STATIC-PIE: "-Bstatic" "-pie" "--no-dynamic-linker" "-z" "text" "-m" "aarch64linux" "-EL"
+// C-ARM-STATIC-PIE: "{{.*}}rcrt1.o"
+// C-ARM-STATIC-PIE: "{{.*}}crtbeginS.o"
+// C-ARM-STATIC-PIE: "--start-group" "-lgcc" "-lgcc_eh" "-lc" "-lgloss" "--end-group"
+// C-ARM-STATIC-PIE: "{{.*}}crtendS.o"
diff --git a/clang/test/Driver/arm-toolchain.c b/clang/test/Driver/arm-toolchain.c
index c367594b0a758..f164fee723e25 100644
--- a/clang/test/Driver/arm-toolchain.c
+++ b/clang/test/Driver/arm-toolchain.c
@@ -158,3 +158,15 @@
 // ARM-BAREMETAL-UNWINDLIB: "{{.*}}clang_rt.crtbegin.o"
 // ARM-BAREMETAL-UNWINDLIB: "--start-group" "{{.*}}libclang_rt.builtins.a" "--as-needed" "-lunwind" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // ARM-BAREMETAL-UNWINDLIB: "{{.*}}clang_rt.crtend.o"
+
+// RUN: %clang -static-pie -### %s -fuse-ld= \
+// RUN:   --target=armv6m-none-eabi --rtlib=libgcc --unwindlib=platform \
+// RUN:   --gcc-toolchain=%S/Inputs/basic_arm_gcc_tree \
+// RUN:   --sysroot=%S/Inputs/basic_arm_gcc_tree/armv6m-none-eabi 2>&1 \
+// RUN:   | FileCheck -check-prefix=C-ARM-STATIC-PIE %s
+
+// C-ARM-STATIC-PIE: "-Bstatic" "-pie" "--no-dynamic-linker" "-z" "text" "-m" "armelf_linux_eabi" "-EL"
+// C-ARM-STATIC-PIE: "{{.*}}rcrt1.o"
+// C-ARM-STATIC-PIE: "{{.*}}crtbeginS.o"
+// C-ARM-STATIC-PIE: "--start-group" "-lgcc" "-lgcc_eh" "-lc" "-lgloss" "--end-group"
+// C-ARM-STATIC-PIE: "{{.*}}crtendS.o"
diff --git a/clang/test/Driver/baremetal.cpp b/clang/test/Driver/baremetal.cpp
index 4dc320191317e..1e86432bb0d43 100644
--- a/clang/test/Driver/baremetal.cpp
+++ b/clang/test/Driver/baremetal.cpp
@@ -591,3 +591,29 @@
 // RUN:     --sysroot=%S/Inputs/basic_riscv64_tree/riscv64-unknown-elf \
 // RUN:   | FileCheck --check-prefix=CHECK-RV64-RELAX %s
 // CHECK-RV64-RELAX-NOT: "--no-relax"
+
+// Check that "-static -pie" is forwarded to linker when "-static-pie" is used
+
+// RUN: %clang -static-pie -### %s 2>&1 \
+// RUN:     --target=armv6m-none-eabi -rtlib=platform --unwindlib=platform \
+// RUN:     --sysroot=%S/Inputs/baremetal_arm \
+// RUN:   | FileCheck --check-prefix=CHECK-CLANG-LD-STATIC-PIE %s
+
+// RUN: %clang -static-pie -### %s 2>&1 \
+// RUN:     --target=aarch64-none-elf -rtlib=platform --unwindlib=platform \
+// RUN:     --sysroot=%S/Inputs/baremetal_arm \
+// RUN:   | FileCheck --check-prefix=CHECK-CLANG-LD-STATIC-PIE %s
+
+// RUN: %clang -static-pie -### %s 2>&1 \
+// RUN:     --target=riscv32-unknown-elf-rtlib=platform --unwindlib=platform \
+// RUN:     --sysroot=%S/Inputs/basic_riscv32_tree/riscv32-unknown-elf \
+// RUN:   | FileCheck --check-prefix=CHECK-CLANG-LD-STATIC-PIE %s
+
+// RUN: %clang -static-pie -### %s 2>&1 \
+// RUN:     --target=riscv64-unknown-elf-rtlib=platform --unwindlib=platform \
+// RUN:     --sysroot=%S/Inputs/basic_riscv32_tree/riscv64-unknown-elf \
+// RUN:   | FileCheck --check-prefix=CHECK-CLANG-LD-STATIC-PIE %s
+
+// CHECK-CLANG-LD-STATIC-PIE: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
+// CHECK-CLANG-LD-STATIC-PIE-SAME: "-static" "-pie" "--no-dynamic-linker" "-z" "text"
+// CHECK-CLANG-LD-STATIC-PIE: "{{.*}}rcrt1.o"
\ No newline at end of file
diff --git a/clang/test/Driver/riscv32-toolchain.c b/clang/test/Driver/riscv32-toolchain.c
index 8cf20aa592a3a..f54e6cf8a6c03 100644
--- a/clang/test/Driver/riscv32-toolchain.c
+++ b/clang/test/Driver/riscv32-toolchain.c
@@ -247,6 +247,19 @@
 // RUN:   | FileCheck -check-prefix=CHECK-RV32-GNU-RELAX %s
 // CHECK-RV32-GNU-RELAX-NOT: "--no-relax"
 
+// Check that "-static -pie" is forwarded to linker when "-static-pie" is used
+// RUN: %clang -static-pie -### %s -fuse-ld= \
+// RUN:   --target=riscv32-unknown-elf -rtlib=platform --unwindlib=platform \
+// RUN:   --gcc-toolchain=%S/Inputs/basic_riscv32_tree \
+// RUN:   --sysroot=%S/Inputs/basic_riscv32_tree/riscv32-unknown-elf 2>&1 \
+// RUN:   | FileCheck -check-prefix=C-RV32-STATIC-PIE %s
+
+// C-RV32-STATIC-PIE: "-Bstatic" "-pie" "--no-dynamic-linker" "-z" "text" "-m" "elf32lriscv" "-X"
+// C-RV32-STATIC-PIE: "{{.*}}rcrt1.o"
+// C-RV32-STATIC-PIE: "{{.*}}crtbeginS.o"
+// C-RV32-STATIC-PIE: "--start-group" "-lgcc" "-lc" "-lgloss" "--end-group"
+// C-RV32-STATIC-PIE: "{{.*}}crtendS.o"
+
 typedef __builtin_va_list va_list;
 typedef __SIZE_TYPE__ size_t;
 typedef __PTRDIFF_TYPE__ ptrdiff_t;
diff --git a/clang/test/Driver/riscv64-toolchain.c b/clang/test/Driver/riscv64-toolchain.c
index 1550f46af8c9c..c3f54bf444ee2 100644
--- a/clang/test/Driver/riscv64-toolchain.c
+++ b/clang/test/Driver/riscv64-toolchain.c
@@ -203,6 +203,19 @@
 // RUN:   | FileCheck -check-prefix=CHECK-RV64-GNU-RELAX %s
 // CHECK-RV64-GNU-RELAX-NOT: "--no-relax"
 
+// Check that "-static -pie" is forwarded to linker when "-static-pie" is used
+// RUN: %clang -static-pie -### %s -fuse-ld= \
+// RUN:   --target=riscv64-unknown-elf -rtlib=platform --unwindlib=platform \
+// RUN:   --gcc-toolchain=%S/Inputs/basic_riscv64_tree \
+// RUN:   --sysroot=%S/Inputs/basic_riscv64_tree/riscv64-unknown-elf 2>&1 \
+// RUN:   | FileCheck -check-prefix=C-RV64-STATIC-PIE %s
+
+// C-RV64-STATIC-PIE: "-Bstatic" "-pie" "--no-dynamic-linker" "-z" "text" "-m" "elf64lriscv" "-X"
+// C-RV64-STATIC-PIE: "{{.*}}rcrt1.o"
+// C-RV64-STATIC-PIE: "{{.*}}crtbeginS.o"
+// C-RV64-STATIC-PIE: "--start-group" "-lgcc" "-lc" "-lgloss" "--end-group"
+// C-RV64-STATIC-PIE: "{{.*}}crtendS.o"
+
 typedef __builtin_va_list va_list;
 typedef __SIZE_TYPE__ size_t;
 typedef __PTRDIFF_TYPE__ ptrdiff_t;

github-actions · 2025-07-08T19:50:28Z

✅ With the latest revision this PR passed the C/C++ code formatter.

toolchain Change-Id: I580875585e9eac2e9568e84650265f71d028f3ff

petrhosek · 2025-07-09T21:21:28Z

clang/lib/Driver/ToolChains/BareMetal.cpp


  if (!D.SysRoot.empty())
    CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));

  CmdArgs.push_back("-Bstatic");
+  if (IsStaticPIE) {
+    CmdArgs.push_back("-pie");
+    CmdArgs.push_back("--no-dynamic-linker");


This is already the default for LLD, is this needed for other linkers like GNU ld?

llvmbot added clang Clang issues not falling into any other category backend:RISC-V clang:driver 'clang' and 'clang++' user-facing binaries. Not 'clang-cl' labels Jul 8, 2025

quic-garvgupt force-pushed the pie branch 2 times, most recently from 7f9e12f to a1f3797 Compare July 8, 2025 19:56

quic-garvgupt requested review from lenary, petrhosek, MaskRay and smithp35 July 8, 2025 19:57

Propogate linker flags when -static-pie is enabled in BareMetal

c6420bc

toolchain Change-Id: I580875585e9eac2e9568e84650265f71d028f3ff

quic-garvgupt force-pushed the pie branch from a1f3797 to c6420bc Compare July 8, 2025 20:04

quic-garvgupt changed the title ~~Propogate linker flags when -static-pie is enabled in BareMetal Toolchain~~ Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain Jul 8, 2025

MaskRay approved these changes Jul 9, 2025

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Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain #147589

Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain #147589

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Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain #147589

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Add necessary linker flags when -static-pie is enabled in BareMetal Toolchain #147589

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