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Merged
merged 1 commit into from
Jun 30, 2025
Merged

Reland [Driver] Fix link order of BareMetal toolchain object #146291

merged 1 commit into from
Jun 30, 2025

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quic-garvgupt
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The linker job in BareMetal toolchain object will be used by GNU ld and lld both.
However, gnuld process the arguments in the order in which they appear on command
line, whereas there is no such restriction with lld.

The previous order was:
LibraryPaths -> Libraries -> LTOOptions -> LinkerInputs The new order is:
LibraryPaths -> LTOOptions -> LinkerInputs -> Libraries

LTO options need to be added before adding any linker inputs because file format
after compile stage during LTO is bitcode which gnuld natively cannot process.
Hence will need to pass appropriate plugins before adding any bitcode file on the
command line.

Object files that are getting linked need to be passed before processing any
libraries so that gnuld can appropriately do symbol resolution for the symbols
for which no definition is provided through user code.

Similar link order is also followed by other linker jobs for gnuld such as in
gnutools::Linker in Gnu.cpp

This is the 3rd patch in the series of patches of merging RISCVToolchain into
BareMetal toolchain object.

RFC:
https: //discourse.llvm.org/t/merging-riscvtoolchain-and-baremetal-toolchains/75524

@quic-garvgupt
Reland [Driver] Fix link order of BareMetal toolchain object (llvm#13…
246f302 
…2806)

The linker job in BareMetal toolchain object will be used by GNU ld and
lld both.
However, gnuld process the arguments in the order in which they appear
on command
line, whereas there is no such restriction with lld.

The previous order was:
LibraryPaths -> Libraries -> LTOOptions -> LinkerInputs
The new order is:
LibraryPaths -> LTOOptions -> LinkerInputs -> Libraries

LTO options need to be added before adding any linker inputs because
file format
after compile stage during LTO is bitcode which gnuld natively cannot
process.
Hence will need to pass appropriate plugins before adding any bitcode
file on the
command line.

Object files that are getting linked need to be passed before processing
any
libraries so that gnuld can appropriately do symbol resolution for the
symbols
for which no definition is provided through user code.

Similar link order is also followed by other linker jobs for gnuld such
as in
gnutools::Linker in Gnu.cpp

This is the 3rd patch in the series of patches of merging RISCVToolchain
into
BareMetal toolchain object.

RFC:

https: //discourse.llvm.org/t/merging-riscvtoolchain-and-baremetal-toolchains/75524
Change-Id: I36848d7858595c88127ef081a16c663e90f65f17
@llvmbot llvmbot added clang Clang issues not falling into any other category clang:driver 'clang' and 'clang++' user-facing binaries. Not 'clang-cl' labels Jun 29, 2025
@llvmbot
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llvmbot commented Jun 29, 2025 •
edited
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@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-driver

Author: Garvit Gupta (quic-garvgupt)

Changes

The linker job in BareMetal toolchain object will be used by GNU ld and lld both.
However, gnuld process the arguments in the order in which they appear on command
line, whereas there is no such restriction with lld.

The previous order was:
LibraryPaths -> Libraries -> LTOOptions -> LinkerInputs The new order is:
LibraryPaths -> LTOOptions -> LinkerInputs -> Libraries

LTO options need to be added before adding any linker inputs because file format
after compile stage during LTO is bitcode which gnuld natively cannot process.
Hence will need to pass appropriate plugins before adding any bitcode file on the
command line.

Object files that are getting linked need to be passed before processing any
libraries so that gnuld can appropriately do symbol resolution for the symbols
for which no definition is provided through user code.

Similar link order is also followed by other linker jobs for gnuld such as in
gnutools::Linker in Gnu.cpp

This is the 3rd patch in the series of patches of merging RISCVToolchain into
BareMetal toolchain object.

RFC:
https: //discourse.llvm.org/t/merging-riscvtoolchain-and-baremetal-toolchains/75524

Patch is 43.44 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/146291.diff

8 Files Affected:

  • (modified) clang/lib/Driver/ToolChains/BareMetal.cpp (+6-6)
  • (modified) clang/test/Driver/aarch64-toolchain-extra.c (+1-1)
  • (modified) clang/test/Driver/aarch64-toolchain.c (+14-14)
  • (modified) clang/test/Driver/arm-toolchain-extra.c (+1-1)
  • (modified) clang/test/Driver/arm-toolchain.c (+14-14)
  • (modified) clang/test/Driver/baremetal-multilib.yaml (+2-1)
  • (modified) clang/test/Driver/baremetal-sysroot.cpp (+5-3)
  • (modified) clang/test/Driver/baremetal.cpp (+49-30)
diff --git a/clang/lib/Driver/ToolChains/BareMetal.cpp b/clang/lib/Driver/ToolChains/BareMetal.cpp
index a08bb588dd764..a665040662a3f 100644
--- a/clang/lib/Driver/ToolChains/BareMetal.cpp
+++ b/clang/lib/Driver/ToolChains/BareMetal.cpp
@@ -568,8 +568,6 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   const llvm::Triple::ArchType Arch = TC.getArch();
   const llvm::Triple &Triple = getToolChain().getEffectiveTriple();
 
-  AddLinkerInputs(TC, Inputs, Args, CmdArgs, JA);
-
   CmdArgs.push_back("-Bstatic");
 
   if (TC.getTriple().isRISCV() && Args.hasArg(options::OPT_mno_relax))
@@ -619,6 +617,12 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   for (const auto &LibPath : TC.getLibraryPaths())
     CmdArgs.push_back(Args.MakeArgString(llvm::Twine("-L", LibPath)));
 
+  if (D.isUsingLTO())
+    addLTOOptions(TC, Args, CmdArgs, Output, Inputs,
+                  D.getLTOMode() == LTOK_Thin);
+
+  AddLinkerInputs(TC, Inputs, Args, CmdArgs, JA);
+
   if (TC.ShouldLinkCXXStdlib(Args)) {
     bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
                                !Args.hasArg(options::OPT_static);
@@ -639,10 +643,6 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("--end-group");
   }
 
-  if (D.isUsingLTO())
-    addLTOOptions(TC, Args, CmdArgs, Output, Inputs,
-                  D.getLTOMode() == LTOK_Thin);
-
   if ((TC.hasValidGCCInstallation() || detectGCCToolchainAdjacent(D)) &&
       NeedCRTs)
     CmdArgs.push_back(Args.MakeArgString(TC.GetFilePath(CRTEnd)));
diff --git a/clang/test/Driver/aarch64-toolchain-extra.c b/clang/test/Driver/aarch64-toolchain-extra.c
index 4b22e35314436..4945a622969c6 100644
--- a/clang/test/Driver/aarch64-toolchain-extra.c
+++ b/clang/test/Driver/aarch64-toolchain-extra.c
@@ -31,5 +31,5 @@
 // C-AARCH64-BAREMETAL-NOGCC: "{{.*}}/aarch64-nogcc/bin/../aarch64-none-elf/lib/crt0.o"
 // C-AARCH64-BAREMETAL-NOGCC: "{{.*}}/aarch64-nogcc/{{.*}}/aarch64-none-elf/lib/crtbegin.o"
 // C-AARCH64-BAREMETAL-NOGCC: "{{.*}}/aarch64-nogcc/bin/../aarch64-none-elf/lib"
-// C-AARCH64-BAREMETAL-NOGCC: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-AARCH64-BAREMETAL-NOGCC: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-AARCH64-BAREMETAL-NOGCC: "{{.*}}/aarch64-nogcc/{{.*}}/aarch64-none-elf/lib/crtend.o"
diff --git a/clang/test/Driver/aarch64-toolchain.c b/clang/test/Driver/aarch64-toolchain.c
index 61a8428afbd51..19afbcf278c17 100644
--- a/clang/test/Driver/aarch64-toolchain.c
+++ b/clang/test/Driver/aarch64-toolchain.c
@@ -11,12 +11,12 @@
 // LLD-AARCH64-BAREMETAL: "-isysroot" "{{.*}}Inputs/basic_aarch64_gcc_tree/aarch64-none-elf"
 // LLD-AARCH64-BAREMETAL: "-internal-isystem" "{{.*}}Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include"
 // LLD-AARCH64-BAREMETAL: "{{.*}}/Inputs/lld/ld.lld"
-// LLD-AARCH64-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// LLD-AARCH64-BAREMETAL: "-Bstatic" "-EL"
 // LLD-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib/crt0.o"
 // LLD-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // LLD-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // LLD-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib"
-// LLD-AARCH64-BAREMETAL: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// LLD-AARCH64-BAREMETAL: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // LLD-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clang -### %s -fuse-ld= \
@@ -29,12 +29,12 @@
 // C-AARCH64-BAREMETAL: "-isysroot" "{{.*}}Inputs/basic_aarch64_gcc_tree/aarch64-none-elf"
 // C-AARCH64-BAREMETAL: "-internal-isystem" "{{.*}}Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include"
 // C-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld"
-// C-AARCH64-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// C-AARCH64-BAREMETAL: "-Bstatic" "-EL"
 // C-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib/crt0.o"
 // C-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // C-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // C-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib"
-// C-AARCH64-BAREMETAL: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-AARCH64-BAREMETAL: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clang -### %s -fuse-ld= \
@@ -46,12 +46,12 @@
 // C-AARCH64-BAREMETAL-NOSYSROOT: "-cc1" "-triple" "aarch64-unknown-none-elf"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/include"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld"
-// C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-Bstatic" "-EL"
+// C-AARCH64-BAREMETAL-NOSYSROOT: "-Bstatic" "-EL"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib/crt0.o"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib"
-// C-AARCH64-BAREMETAL-NOSYSROOT: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -65,12 +65,12 @@
 // CXX-AARCH64-BAREMETAL: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include/c++/8.2.1"
 // CXX-AARCH64-BAREMETAL: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include"
 // CXX-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld"
-// CXX-AARCH64-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-AARCH64-BAREMETAL: "-Bstatic" "-EL"
 // CXX-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib/crt0.o"
 // CXX-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // CXX-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // CXX-AARCH64-BAREMETAL: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib"
-// CXX-AARCH64-BAREMETAL: "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-AARCH64-BAREMETAL: "{{.*}}.o" "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-AARCH64-BAREMETAL: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -84,12 +84,12 @@
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/include/c++/8.2.1"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/include"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld"
-// CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-AARCH64-BAREMETAL-NOSYSROOT: "-Bstatic" "-EL"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib/crt0.o"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib"
-// CXX-AARCH64-BAREMETAL-NOSYSROOT: "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -102,12 +102,12 @@
 // CXX-AARCH64-BAREMETAL-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include/c++/v1"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/include"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld
-// CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-AARCH64-BAREMETAL-LIBCXX: "-Bstatic" "-EL"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib/crt0.o"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/aarch64-none-elf/lib"
-// CXX-AARCH64-BAREMETAL-LIBCXX: "-lc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}.o" "-lc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-AARCH64-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -119,12 +119,12 @@
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/include/c++/v1"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/include"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../bin/aarch64-none-elf-ld"
-// CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-Bstatic" "-EL"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib/crt0.o"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtbegin.o"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-L{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/../../../../aarch64-none-elf/lib"
-// CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "-lc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}.o" "-lc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-AARCH64-BAREMETAL-NOSYSROOT-LIBCXX: "{{.*}}/Inputs/basic_aarch64_gcc_tree/lib/gcc/aarch64-none-elf/8.2.1/crtend.o"
 
 // RUN: %clang -### %s -fuse-ld= \
diff --git a/clang/test/Driver/arm-toolchain-extra.c b/clang/test/Driver/arm-toolchain-extra.c
index b6d64ab7625b3..43cca6112176c 100644
--- a/clang/test/Driver/arm-toolchain-extra.c
+++ b/clang/test/Driver/arm-toolchain-extra.c
@@ -31,6 +31,6 @@
 // C-ARM-BAREMETAL-NOGCC: "{{.*}}/arm-nogcc/bin/../armv6m-none-eabi/lib/crt0.o"
 // C-ARM-BAREMETAL-NOGCC: "{{.*}}/arm-nogcc/{{.*}}/armv6m-none-eabi/lib/crtbegin.o"
 // C-ARM-BAREMETAL-NOGCC: "{{.*}}/arm-nogcc/bin/../armv6m-none-eabi/lib"
-// C-ARM-BAREMETAL-NOGCC: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-ARM-BAREMETAL-NOGCC: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-ARM-BAREMETAL-NOGCC: "{{.*}}/arm-nogcc/{{.*}}/armv6m-none-eabi/lib/crtend.o"
 
diff --git a/clang/test/Driver/arm-toolchain.c b/clang/test/Driver/arm-toolchain.c
index fd7d2b8d377a3..b600efd846f0e 100644
--- a/clang/test/Driver/arm-toolchain.c
+++ b/clang/test/Driver/arm-toolchain.c
@@ -10,12 +10,12 @@
 // LLD-ARM-BAREMETAL: "-isysroot" "{{.*}}Inputs/basic_arm_gcc_tree/armv6m-none-eabi"
 // LLD-ARM-BAREMETAL: "-internal-isystem" "{{.*}}Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include"
 // LLD-ARM-BAREMETAL: "{{.*}}/Inputs/lld/ld.lld"
-// LLD-ARM-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// LLD-ARM-BAREMETAL: "-Bstatic" "-EL"
 // LLD-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib/crt0.o"
 // LLD-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // LLD-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // LLD-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib"
-// LLD-ARM-BAREMETAL: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// LLD-ARM-BAREMETAL: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // LLD-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtend.o"
 
 // RUN: %clang -### %s -fuse-ld= \
@@ -28,12 +28,12 @@
 // C-ARM-BAREMETAL: "-isysroot" "{{.*}}Inputs/basic_arm_gcc_tree/armv6m-none-eabi"
 // C-ARM-BAREMETAL: "-internal-isystem" "{{.*}}Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include"
 // C-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../bin/armv6m-none-eabi-ld"
-// C-ARM-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// C-ARM-BAREMETAL: "-Bstatic" "-EL"
 // C-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib/crt0.o"
 // C-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // C-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // C-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib"
-// C-ARM-BAREMETAL: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-ARM-BAREMETAL: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtend.o"
 
 // RUN: %clang -### %s -fuse-ld= \
@@ -45,12 +45,12 @@
 // C-ARM-BAREMETAL-NOSYSROOT: "-cc1" "-triple" "thumbv6m-unknown-none-eabi"
 // C-ARM-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/include"
 // C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../bin/armv6m-none-eabi-ld"
-// C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-Bstatic" "-EL"
+// C-ARM-BAREMETAL-NOSYSROOT: "-Bstatic" "-EL"
 // C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/lib/crt0.o"
 // C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // C-ARM-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // C-ARM-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/lib"
-// C-ARM-BAREMETAL-NOSYSROOT: "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
+// C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}.o" "--start-group" "-lgcc" "--as-needed" "-lgcc_s" "--no-as-needed" "-lc" "-lgloss" "--end-group"
 // C-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -65,12 +65,12 @@
 // CXX-ARM-BAREMETAL: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include/c++/8.2.1"
 // CXX-ARM-BAREMETAL: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include"
 // CXX-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../bin/armv6m-none-eabi-ld"
-// CXX-ARM-BAREMETAL: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-ARM-BAREMETAL: "-Bstatic" "-EL"
 // CXX-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib/crt0.o"
 // CXX-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // CXX-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // CXX-ARM-BAREMETAL: "-L{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib"
-// CXX-ARM-BAREMETAL: "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-ARM-BAREMETAL: "{{.*}}.o" "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-ARM-BAREMETAL: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtend.o"
 
 
@@ -85,12 +85,12 @@
 // CXX-ARM-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/include/c++/8.2.1"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/include"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../bin/armv6m-none-eabi-ld"
-// CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-ARM-BAREMETAL-NOSYSROOT: "-Bstatic" "-EL"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/lib/crt0.o"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../armv6m-none-eabi/lib"
-// CXX-ARM-BAREMETAL-NOSYSROOT: "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
+// CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}.o" "-lstdc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-lgloss" "--end-group"
 // CXX-ARM-BAREMETAL-NOSYSROOT: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtend.o"
 
 // RUN: %clangxx -### %s -fuse-ld= \
@@ -103,12 +103,12 @@
 // CXX-ARM-BAREMETAL-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include/c++/v1"
 // CXX-ARM-BAREMETAL-LIBCXX: "-internal-isystem" "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/include"
 // CXX-ARM-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/../../../../bin/armv6m-none-eabi-ld"
-// CXX-ARM-BAREMETAL-LIBCXX: "{{.*}}.o" "-Bstatic" "-EL"
+// CXX-ARM-BAREMETAL-LIBCXX: "-Bstatic" "-EL"
 // CXX-ARM-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib/crt0.o"
 // CXX-ARM-BAREMETAL-LIBCXX: "{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1/crtbegin.o"
 // CXX-ARM-BAREMETAL-LIBCXX: "-L{{.*}}/Inputs/basic_arm_gcc_tree/lib/gcc/armv6m-none-eabi/8.2.1"
 // CXX-ARM-BAREMETAL-LIBCXX: "-L{{.*}}/Inputs/basic_arm_gcc_tree/armv6m-none-eabi/lib"
-// CXX-ARM-BAREMETAL-LIBCXX: "-lc++" "-lm" "--start-group" "-lgcc_s" "-lgcc" "-lc" "-l...
[truncated]

@quic-garvgupt quic-garvgupt merged commit a17f635 into llvm:main Jun 30, 2025
10 checks passed
rlavaee pushed a commit to rlavaee/llvm-project that referenced this pull request Jul 1, 2025
@quic-garvgupt @rlavaee
Reland [Driver] Fix link order of BareMetal toolchain object (llvm#14…
085e99c 
…6291)

The linker job in BareMetal toolchain object will be used by GNU ld and
lld both.
However, gnuld process the arguments in the order in which they appear
on command
line, whereas there is no such restriction with lld.

The previous order was:
LibraryPaths -> Libraries -> LTOOptions -> LinkerInputs The new order
is:
LibraryPaths -> LTOOptions -> LinkerInputs -> Libraries

LTO options need to be added before adding any linker inputs because
file format
after compile stage during LTO is bitcode which gnuld natively cannot
process.
Hence will need to pass appropriate plugins before adding any bitcode
file on the
command line.

Object files that are getting linked need to be passed before processing
any
libraries so that gnuld can appropriately do symbol resolution for the
symbols
for which no definition is provided through user code.

Similar link order is also followed by other linker jobs for gnuld such
as in
gnutools::Linker in Gnu.cpp

This is the 3rd patch in the series of patches of merging RISCVToolchain
into
BareMetal toolchain object.

RFC:
https:
//discourse.llvm.org/t/merging-riscvtoolchain-and-baremetal-toolchains/75524
rlavaee pushed a commit to rlavaee/llvm-project that referenced this pull request Jul 1, 2025
@quic-garvgupt @rlavaee
Reland [Driver] Fix link order of BareMetal toolchain object (llvm#14…
0af0355 
…6291)

The linker job in BareMetal toolchain object will be used by GNU ld and
lld both.
However, gnuld process the arguments in the order in which they appear
on command
line, whereas there is no such restriction with lld.

The previous order was:
LibraryPaths -> Libraries -> LTOOptions -> LinkerInputs The new order
is:
LibraryPaths -> LTOOptions -> LinkerInputs -> Libraries

LTO options need to be added before adding any linker inputs because
file format
after compile stage during LTO is bitcode which gnuld natively cannot
process.
Hence will need to pass appropriate plugins before adding any bitcode
file on the
command line.

Object files that are getting linked need to be passed before processing
any
libraries so that gnuld can appropriately do symbol resolution for the
symbols
for which no definition is provided through user code.

Similar link order is also followed by other linker jobs for gnuld such
as in
gnutools::Linker in Gnu.cpp

This is the 3rd patch in the series of patches of merging RISCVToolchain
into
BareMetal toolchain object.

RFC:
https:
//discourse.llvm.org/t/merging-riscvtoolchain-and-baremetal-toolchains/75524
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