[Clang][Driver] Revise Cygwin ToolChain to call linker directly #147960
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@llvm/pr-subscribers-clang Author: None (tyan0) Changes...so that Full diff: https://github.com/llvm/llvm-project/pull/147960.diff 9 Files Affected:
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 3f9b808b2722e..3c9148ee51fd0 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -684,6 +684,8 @@ static StringRef getArchNameForCompilerRTLib(const ToolChain &TC,
StringRef ToolChain::getOSLibName() const {
if (Triple.isOSDarwin())
return "darwin";
+ if (Triple.isWindowsCygwinEnvironment())
+ return "cygwin";
switch (Triple.getOS()) {
case llvm::Triple::FreeBSD:
@@ -1504,6 +1506,7 @@ void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
switch (Type) {
case ToolChain::CST_Libcxx:
CmdArgs.push_back("-lc++");
+ CmdArgs.push_back("-lc++abi");
if (Args.hasArg(options::OPT_fexperimental_library))
CmdArgs.push_back("-lc++experimental");
break;
diff --git a/clang/lib/Driver/ToolChains/Cygwin.cpp b/clang/lib/Driver/ToolChains/Cygwin.cpp
index d9c16347daa34..82a88065b0c9d 100644
--- a/clang/lib/Driver/ToolChains/Cygwin.cpp
+++ b/clang/lib/Driver/ToolChains/Cygwin.cpp
@@ -9,6 +9,7 @@
#include "Cygwin.h"
#include "clang/Config/config.h"
#include "clang/Driver/CommonArgs.h"
+#include "clang/Driver/Compilation.h"
#include "clang/Driver/Driver.h"
#include "clang/Driver/Options.h"
#include "llvm/Support/Path.h"
@@ -30,6 +31,8 @@ Cygwin::Cygwin(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
Generic_GCC::PushPPaths(PPaths);
path_list &Paths = getFilePaths();
+ if (GCCInstallation.isValid())
+ Paths.push_back(GCCInstallation.getInstallPath().str());
Generic_GCC::AddMultiarchPaths(D, SysRoot, "lib", Paths);
@@ -107,3 +110,289 @@ void Cygwin::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include");
addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include/w32api");
}
+
+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);
+}
+
+void cygwin::Linker::ConstructJob(Compilation &C, const JobAction &JA,
+ const InputInfo &Output,
+ const InputInfoList &Inputs,
+ const ArgList &Args,
+ const char *LinkingOutput) const {
+ const auto &ToolChain = static_cast<const Cygwin &>(getToolChain());
+ const Driver &D = ToolChain.getDriver();
+
+ const bool IsIAMCU = ToolChain.getTriple().isOSIAMCU();
+ const bool IsVE = ToolChain.getTriple().isVE();
+ const bool IsStaticPIE = getStaticPIE(Args, ToolChain);
+ const bool IsStatic = getStatic(Args);
+
+ ArgStringList CmdArgs;
+
+ // Silence warning for "clang -g foo.o -o foo"
+ Args.ClaimAllArgs(options::OPT_g_Group);
+ // and "clang -emit-llvm foo.o -o foo"
+ Args.ClaimAllArgs(options::OPT_emit_llvm);
+ // and for "clang -w foo.o -o foo". Other warning options are already
+ // handled somewhere else.
+ Args.ClaimAllArgs(options::OPT_w);
+
+ if (!D.SysRoot.empty())
+ CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
+
+ if (Args.hasArg(options::OPT_s))
+ CmdArgs.push_back("-s");
+
+ CmdArgs.push_back("-m");
+ switch (ToolChain.getArch()) {
+ case llvm::Triple::x86:
+ CmdArgs.push_back("i386pe");
+ break;
+ case llvm::Triple::x86_64:
+ CmdArgs.push_back("i386pep");
+ break;
+ case llvm::Triple::arm:
+ case llvm::Triple::thumb:
+ // FIXME: this is incorrect for WinCE
+ CmdArgs.push_back("thumb2pe");
+ break;
+ case llvm::Triple::aarch64:
+ if (ToolChain.getEffectiveTriple().isWindowsArm64EC())
+ CmdArgs.push_back("arm64ecpe");
+ else
+ CmdArgs.push_back("arm64pe");
+ break;
+ default:
+ D.Diag(diag::err_target_unknown_triple) << ToolChain.getEffectiveTriple().str();
+ }
+
+ CmdArgs.push_back("--wrap=_Znwm");
+ CmdArgs.push_back("--wrap=_Znam");
+ CmdArgs.push_back("--wrap=_ZdlPv");
+ CmdArgs.push_back("--wrap=_ZdaPv");
+ CmdArgs.push_back("--wrap=_ZnwmRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZnamRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZdlPvRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZdaPvRKSt9nothrow_t");
+
+ const bool IsShared = Args.hasArg(options::OPT_shared);
+ if (IsShared)
+ CmdArgs.push_back("-shared");
+ bool IsPIE = false;
+ if (IsStaticPIE) {
+ CmdArgs.push_back("-static");
+ CmdArgs.push_back("-pie");
+ CmdArgs.push_back("--no-dynamic-linker");
+ CmdArgs.push_back("-z");
+ CmdArgs.push_back("text");
+ } else if (IsStatic) {
+ CmdArgs.push_back("-static");
+ } else if (!Args.hasArg(options::OPT_r)) {
+ if (Args.hasArg(options::OPT_rdynamic))
+ CmdArgs.push_back("-export-dynamic");
+ if (!IsShared) {
+ IsPIE = Args.hasFlag(options::OPT_pie, options::OPT_no_pie,
+ ToolChain.isPIEDefault(Args));
+ if (IsPIE)
+ CmdArgs.push_back("-pie");
+ }
+ }
+
+ CmdArgs.push_back("-o");
+ CmdArgs.push_back(Output.getFilename());
+
+ if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles,
+ options::OPT_r)) {
+ if (IsVE) {
+ CmdArgs.push_back("-z");
+ CmdArgs.push_back("max-page-size=0x4000000");
+ }
+
+ if (IsShared) {
+ CmdArgs.push_back("-e");
+ CmdArgs.push_back("_cygwin_dll_entry");
+ CmdArgs.push_back("--enable-auto-image-base");
+ }
+
+ if (!IsShared)
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt0.o")));
+ if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT) {
+ std::string crtbegin = ToolChain.getCompilerRT(Args, "crtbegin",
+ ToolChain::FT_Object);
+ if (ToolChain.getVFS().exists(crtbegin)) {
+ std::string P;
+ P = crtbegin;
+ CmdArgs.push_back(Args.MakeArgString(P));
+ }
+ }
+ if (IsShared)
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtbeginS.o")));
+ else
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtbegin.o")));
+
+ // Add crtfastmath.o if available and fast math is enabled.
+ ToolChain.addFastMathRuntimeIfAvailable(Args, CmdArgs);
+ }
+
+ Args.addAllArgs(CmdArgs, {options::OPT_L, options::OPT_u});
+
+ ToolChain.AddFilePathLibArgs(Args, CmdArgs);
+
+ CmdArgs.push_back(Args.MakeArgString(
+ "-L" + ToolChain.getGCCInstallation().getInstallPath()));
+
+ if (D.isUsingLTO()) {
+ assert(!Inputs.empty() && "Must have at least one input.");
+ // Find the first filename InputInfo object.
+ auto Input = llvm::find_if(
+ Inputs, [](const InputInfo &II) -> bool { return II.isFilename(); });
+ if (Input == Inputs.end())
+ // For a very rare case, all of the inputs to the linker are
+ // InputArg. If that happens, just use the first InputInfo.
+ Input = Inputs.begin();
+
+ tools::addLTOOptions(ToolChain, Args, CmdArgs, Output, *Input,
+ D.getLTOMode() == LTOK_Thin);
+ }
+
+ if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
+ CmdArgs.push_back("--no-demangle");
+
+ bool NeedsSanitizerDeps = tools::addSanitizerRuntimes(ToolChain, Args, CmdArgs);
+ bool NeedsXRayDeps = tools::addXRayRuntime(ToolChain, Args, CmdArgs);
+ tools::addLinkerCompressDebugSectionsOption(ToolChain, Args, CmdArgs);
+ tools::AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
+
+ tools::addHIPRuntimeLibArgs(ToolChain, C, Args, CmdArgs);
+
+ // The profile runtime also needs access to system libraries.
+ getToolChain().addProfileRTLibs(Args, CmdArgs);
+
+ if (D.CCCIsCXX() &&
+ !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs,
+ options::OPT_r)) {
+ if (ToolChain.ShouldLinkCXXStdlib(Args)) {
+ bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
+ !Args.hasArg(options::OPT_static);
+ if (OnlyLibstdcxxStatic)
+ CmdArgs.push_back("-Bstatic");
+ ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+ if (OnlyLibstdcxxStatic)
+ CmdArgs.push_back("-Bdynamic");
+ }
+ CmdArgs.push_back("-lm");
+ }
+
+ // Silence warnings when linking C code with a C++ '-stdlib' argument.
+ Args.ClaimAllArgs(options::OPT_stdlib_EQ);
+
+ // Additional linker set-up and flags for Fortran. This is required in order
+ // to generate executables. As Fortran runtime depends on the C runtime,
+ // these dependencies need to be listed before the C runtime below (i.e.
+ // AddRunTimeLibs).
+ if (D.IsFlangMode() &&
+ !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
+ tools::addFortranRuntimeLibraryPath(ToolChain, Args, CmdArgs);
+ tools::addFortranRuntimeLibs(ToolChain, Args, CmdArgs);
+ CmdArgs.push_back("-lm");
+ }
+
+ if (!Args.hasArg(options::OPT_nostdlib, options::OPT_r)) {
+ if (!Args.hasArg(options::OPT_nodefaultlibs)) {
+ if (IsStatic || IsStaticPIE)
+ CmdArgs.push_back("--start-group");
+
+ if (NeedsSanitizerDeps)
+ tools::linkSanitizerRuntimeDeps(ToolChain, Args, CmdArgs);
+
+ if (NeedsXRayDeps)
+ tools::linkXRayRuntimeDeps(ToolChain, Args, CmdArgs);
+
+ bool WantPthread = Args.hasArg(options::OPT_pthread) ||
+ Args.hasArg(options::OPT_pthreads);
+
+ // Use the static OpenMP runtime with -static-openmp
+ bool StaticOpenMP = Args.hasArg(options::OPT_static_openmp) &&
+ !Args.hasArg(options::OPT_static);
+
+ // FIXME: Only pass GompNeedsRT = true for platforms with libgomp that
+ // require librt. Most modern Linux platforms do, but some may not.
+ if (tools::addOpenMPRuntime(C, CmdArgs, ToolChain, Args, StaticOpenMP,
+ JA.isHostOffloading(Action::OFK_OpenMP),
+ /* GompNeedsRT= */ true))
+ // OpenMP runtimes implies pthreads when using the GNU toolchain.
+ // FIXME: Does this really make sense for all GNU toolchains?
+ WantPthread = true;
+
+ tools::AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+
+ if (WantPthread)
+ CmdArgs.push_back("-lpthread");
+
+ if (Args.hasArg(options::OPT_fsplit_stack))
+ CmdArgs.push_back("--wrap=pthread_create");
+
+ if (!Args.hasArg(options::OPT_nolibc))
+ CmdArgs.push_back("-lc");
+
+ // Cygwin specific
+ CmdArgs.push_back("-lcygwin");
+ CmdArgs.push_back("-ladvapi32");
+ CmdArgs.push_back("-lshell32");
+ CmdArgs.push_back("-luser32");
+ CmdArgs.push_back("-lkernel32");
+
+ // Add IAMCU specific libs, if needed.
+ if (IsIAMCU)
+ CmdArgs.push_back("-lgloss");
+
+ if (IsStatic || IsStaticPIE)
+ CmdArgs.push_back("--end-group");
+ else
+ tools::AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+
+ // Add IAMCU specific libs (outside the group), if needed.
+ if (IsIAMCU) {
+ CmdArgs.push_back("--as-needed");
+ CmdArgs.push_back("-lsoftfp");
+ CmdArgs.push_back("--no-as-needed");
+ }
+ }
+
+ if (!Args.hasArg(options::OPT_nostartfiles) && !IsIAMCU) {
+ if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT) {
+ std::string crtend = ToolChain.getCompilerRT(Args, "crtend",
+ ToolChain::FT_Object);
+ if (ToolChain.getVFS().exists(crtend)) {
+ std::string P;
+ P = crtend;
+ CmdArgs.push_back(Args.MakeArgString(P));
+ }
+ }
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
+ }
+ }
+
+ Args.addAllArgs(CmdArgs, {options::OPT_T, options::OPT_t});
+
+ const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
+ C.addCommand(std::make_unique<Command>(JA, *this,
+ ResponseFileSupport::AtFileCurCP(),
+ Exec, CmdArgs, Inputs, Output));
+}
+
+auto Cygwin::buildLinker() const -> Tool * { return new cygwin::Linker(*this); }
diff --git a/clang/lib/Driver/ToolChains/Cygwin.h b/clang/lib/Driver/ToolChains/Cygwin.h
index d2f72c10c3b01..b76069fba6741 100644
--- a/clang/lib/Driver/ToolChains/Cygwin.h
+++ b/clang/lib/Driver/ToolChains/Cygwin.h
@@ -27,7 +27,28 @@ class LLVM_LIBRARY_VISIBILITY Cygwin : public Generic_GCC {
void
AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
llvm::opt::ArgStringList &CC1Args) const override;
+
+ const GCCInstallationDetector &
+ getGCCInstallation() const { return GCCInstallation; };
+
+protected:
+ Tool *buildLinker() const override;
+};
+
+namespace cygwin {
+class LLVM_LIBRARY_VISIBILITY Linker final : public Tool {
+public:
+ Linker(const ToolChain &TC) : Tool("cygwin::Linker", "linker", TC) {}
+
+ bool hasIntegratedCPP() const override { return false; }
+ bool isLinkJob() const override { return true; }
+
+ void ConstructJob(Compilation &C, const JobAction &JA,
+ const InputInfo &Output, const InputInfoList &Inputs,
+ const llvm::opt::ArgList &TCArgs,
+ const char *LinkingOutput) const override;
};
+} // end namespace cygwin
} // end namespace toolchains
} // end namespace driver
diff --git a/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/i686-pc-msys/10/crtend.o b/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/i686-pc-msys/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/x86_64-pc-cygwin/10/crtend.o b/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/x86_64-pc-cygwin/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/crt0.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/crt0.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/i686-pc-cygwin/10/crtend.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/i686-pc-cygwin/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/x86_64-pc-msys/10/crtend.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/x86_64-pc-msys/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/cygwin.cpp b/clang/test/Driver/cygwin.cpp
index dd75c48ddc6b3..8677e84c033fd 100644
--- a/clang/test/Driver/cygwin.cpp
+++ b/clang/test/Driver/cygwin.cpp
@@ -15,19 +15,19 @@
// CHECK-SAME: {{^}} "-internal-externc-isystem" "[[SYSROOT]]/usr/include/w32api"
// CHECK-SAME: "-femulated-tls"
// CHECK-SAME: "-exception-model=dwarf"
-// CHECK: "{{.*}}gcc{{(\.exe)?}}"
-// CHECK-SAME: "-m32"
+// CHECK: "{{.*}}ld{{(\.exe)?}}"
+// CHECK-SAME: "-m" "i386pe"
// RUN: %clang -### %s --target=i686-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: --stdlib=platform -static 2>&1 | FileCheck --check-prefix=CHECK-STATIC %s
// CHECK-STATIC: "-cc1" "-triple" "i686-pc-windows-cygnus"
// CHECK-STATIC-SAME: "-static-define"
-// CHECK-STATIC: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-STATIC: "{{.*}}ld{{(\.exe)?}}"
// CHECK-STATIC-SAME: "-static"
// RUN: %clang -### %s --target=i686-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: -shared 2>&1 | FileCheck --check-prefix=CHECK-SHARED %s
-// CHECK-SHARED: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-SHARED: "{{.*}}ld{{(\.exe)?}}"
// CHECK-SHARED-SAME: "-shared"
// RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
@@ -54,19 +54,19 @@
// CHECK-64-SAME: {{^}} "-internal-externc-isystem" "[[SYSROOT]]/usr/include/w32api"
// CHECK-64-SAME: "-femulated-tls"
// CHECK-64-SAME: "-exception-model=seh"
-// CHECK-64: "{{.*}}gcc{{(\.exe)?}}"
-// CHECK-64-SAME: "-m64"
+// CHECK-64: "{{.*}}ld{{(\.exe)?}}"
+// CHECK-64-SAME: "-m" "i386pep"
// RUN: %clang -### %s --target=x86_64-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: --stdlib=platform -static 2>&1 | FileCheck --check-prefix=CHECK-64-STATIC %s
// CHECK-64-STATIC: "-cc1" "-triple" "x86_64-pc-windows-cygnus"
// CHECK-64-STATIC-SAME: "-static-define"
-// CHECK-64-STATIC: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-64-STATIC: "{{.*}}ld{{(\.exe)?}}"
// CHECK-64-STATIC-SAME: "-static"
// RUN: %clang -### %s --target=x86_64-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: -shared 2>&1 | FileCheck --check-prefix=CHECK-64-SHARED %s
-// CHECK-64-SHARED: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-64-SHARED: "{{.*}}ld{{(\.exe)?}}"
// CHECK-64-SHARED-SAME: "-shared"
// RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
|
|
@llvm/pr-subscribers-clang-driver Author: None (tyan0) Changes...so that Full diff: https://github.com/llvm/llvm-project/pull/147960.diff 9 Files Affected:
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 3f9b808b2722e..3c9148ee51fd0 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -684,6 +684,8 @@ static StringRef getArchNameForCompilerRTLib(const ToolChain &TC,
StringRef ToolChain::getOSLibName() const {
if (Triple.isOSDarwin())
return "darwin";
+ if (Triple.isWindowsCygwinEnvironment())
+ return "cygwin";
switch (Triple.getOS()) {
case llvm::Triple::FreeBSD:
@@ -1504,6 +1506,7 @@ void ToolChain::AddCXXStdlibLibArgs(const ArgList &Args,
switch (Type) {
case ToolChain::CST_Libcxx:
CmdArgs.push_back("-lc++");
+ CmdArgs.push_back("-lc++abi");
if (Args.hasArg(options::OPT_fexperimental_library))
CmdArgs.push_back("-lc++experimental");
break;
diff --git a/clang/lib/Driver/ToolChains/Cygwin.cpp b/clang/lib/Driver/ToolChains/Cygwin.cpp
index d9c16347daa34..82a88065b0c9d 100644
--- a/clang/lib/Driver/ToolChains/Cygwin.cpp
+++ b/clang/lib/Driver/ToolChains/Cygwin.cpp
@@ -9,6 +9,7 @@
#include "Cygwin.h"
#include "clang/Config/config.h"
#include "clang/Driver/CommonArgs.h"
+#include "clang/Driver/Compilation.h"
#include "clang/Driver/Driver.h"
#include "clang/Driver/Options.h"
#include "llvm/Support/Path.h"
@@ -30,6 +31,8 @@ Cygwin::Cygwin(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
Generic_GCC::PushPPaths(PPaths);
path_list &Paths = getFilePaths();
+ if (GCCInstallation.isValid())
+ Paths.push_back(GCCInstallation.getInstallPath().str());
Generic_GCC::AddMultiarchPaths(D, SysRoot, "lib", Paths);
@@ -107,3 +110,289 @@ void Cygwin::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include");
addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include/w32api");
}
+
+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);
+}
+
+void cygwin::Linker::ConstructJob(Compilation &C, const JobAction &JA,
+ const InputInfo &Output,
+ const InputInfoList &Inputs,
+ const ArgList &Args,
+ const char *LinkingOutput) const {
+ const auto &ToolChain = static_cast<const Cygwin &>(getToolChain());
+ const Driver &D = ToolChain.getDriver();
+
+ const bool IsIAMCU = ToolChain.getTriple().isOSIAMCU();
+ const bool IsVE = ToolChain.getTriple().isVE();
+ const bool IsStaticPIE = getStaticPIE(Args, ToolChain);
+ const bool IsStatic = getStatic(Args);
+
+ ArgStringList CmdArgs;
+
+ // Silence warning for "clang -g foo.o -o foo"
+ Args.ClaimAllArgs(options::OPT_g_Group);
+ // and "clang -emit-llvm foo.o -o foo"
+ Args.ClaimAllArgs(options::OPT_emit_llvm);
+ // and for "clang -w foo.o -o foo". Other warning options are already
+ // handled somewhere else.
+ Args.ClaimAllArgs(options::OPT_w);
+
+ if (!D.SysRoot.empty())
+ CmdArgs.push_back(Args.MakeArgString("--sysroot=" + D.SysRoot));
+
+ if (Args.hasArg(options::OPT_s))
+ CmdArgs.push_back("-s");
+
+ CmdArgs.push_back("-m");
+ switch (ToolChain.getArch()) {
+ case llvm::Triple::x86:
+ CmdArgs.push_back("i386pe");
+ break;
+ case llvm::Triple::x86_64:
+ CmdArgs.push_back("i386pep");
+ break;
+ case llvm::Triple::arm:
+ case llvm::Triple::thumb:
+ // FIXME: this is incorrect for WinCE
+ CmdArgs.push_back("thumb2pe");
+ break;
+ case llvm::Triple::aarch64:
+ if (ToolChain.getEffectiveTriple().isWindowsArm64EC())
+ CmdArgs.push_back("arm64ecpe");
+ else
+ CmdArgs.push_back("arm64pe");
+ break;
+ default:
+ D.Diag(diag::err_target_unknown_triple) << ToolChain.getEffectiveTriple().str();
+ }
+
+ CmdArgs.push_back("--wrap=_Znwm");
+ CmdArgs.push_back("--wrap=_Znam");
+ CmdArgs.push_back("--wrap=_ZdlPv");
+ CmdArgs.push_back("--wrap=_ZdaPv");
+ CmdArgs.push_back("--wrap=_ZnwmRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZnamRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZdlPvRKSt9nothrow_t");
+ CmdArgs.push_back("--wrap=_ZdaPvRKSt9nothrow_t");
+
+ const bool IsShared = Args.hasArg(options::OPT_shared);
+ if (IsShared)
+ CmdArgs.push_back("-shared");
+ bool IsPIE = false;
+ if (IsStaticPIE) {
+ CmdArgs.push_back("-static");
+ CmdArgs.push_back("-pie");
+ CmdArgs.push_back("--no-dynamic-linker");
+ CmdArgs.push_back("-z");
+ CmdArgs.push_back("text");
+ } else if (IsStatic) {
+ CmdArgs.push_back("-static");
+ } else if (!Args.hasArg(options::OPT_r)) {
+ if (Args.hasArg(options::OPT_rdynamic))
+ CmdArgs.push_back("-export-dynamic");
+ if (!IsShared) {
+ IsPIE = Args.hasFlag(options::OPT_pie, options::OPT_no_pie,
+ ToolChain.isPIEDefault(Args));
+ if (IsPIE)
+ CmdArgs.push_back("-pie");
+ }
+ }
+
+ CmdArgs.push_back("-o");
+ CmdArgs.push_back(Output.getFilename());
+
+ if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles,
+ options::OPT_r)) {
+ if (IsVE) {
+ CmdArgs.push_back("-z");
+ CmdArgs.push_back("max-page-size=0x4000000");
+ }
+
+ if (IsShared) {
+ CmdArgs.push_back("-e");
+ CmdArgs.push_back("_cygwin_dll_entry");
+ CmdArgs.push_back("--enable-auto-image-base");
+ }
+
+ if (!IsShared)
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt0.o")));
+ if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT) {
+ std::string crtbegin = ToolChain.getCompilerRT(Args, "crtbegin",
+ ToolChain::FT_Object);
+ if (ToolChain.getVFS().exists(crtbegin)) {
+ std::string P;
+ P = crtbegin;
+ CmdArgs.push_back(Args.MakeArgString(P));
+ }
+ }
+ if (IsShared)
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtbeginS.o")));
+ else
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtbegin.o")));
+
+ // Add crtfastmath.o if available and fast math is enabled.
+ ToolChain.addFastMathRuntimeIfAvailable(Args, CmdArgs);
+ }
+
+ Args.addAllArgs(CmdArgs, {options::OPT_L, options::OPT_u});
+
+ ToolChain.AddFilePathLibArgs(Args, CmdArgs);
+
+ CmdArgs.push_back(Args.MakeArgString(
+ "-L" + ToolChain.getGCCInstallation().getInstallPath()));
+
+ if (D.isUsingLTO()) {
+ assert(!Inputs.empty() && "Must have at least one input.");
+ // Find the first filename InputInfo object.
+ auto Input = llvm::find_if(
+ Inputs, [](const InputInfo &II) -> bool { return II.isFilename(); });
+ if (Input == Inputs.end())
+ // For a very rare case, all of the inputs to the linker are
+ // InputArg. If that happens, just use the first InputInfo.
+ Input = Inputs.begin();
+
+ tools::addLTOOptions(ToolChain, Args, CmdArgs, Output, *Input,
+ D.getLTOMode() == LTOK_Thin);
+ }
+
+ if (Args.hasArg(options::OPT_Z_Xlinker__no_demangle))
+ CmdArgs.push_back("--no-demangle");
+
+ bool NeedsSanitizerDeps = tools::addSanitizerRuntimes(ToolChain, Args, CmdArgs);
+ bool NeedsXRayDeps = tools::addXRayRuntime(ToolChain, Args, CmdArgs);
+ tools::addLinkerCompressDebugSectionsOption(ToolChain, Args, CmdArgs);
+ tools::AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
+
+ tools::addHIPRuntimeLibArgs(ToolChain, C, Args, CmdArgs);
+
+ // The profile runtime also needs access to system libraries.
+ getToolChain().addProfileRTLibs(Args, CmdArgs);
+
+ if (D.CCCIsCXX() &&
+ !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs,
+ options::OPT_r)) {
+ if (ToolChain.ShouldLinkCXXStdlib(Args)) {
+ bool OnlyLibstdcxxStatic = Args.hasArg(options::OPT_static_libstdcxx) &&
+ !Args.hasArg(options::OPT_static);
+ if (OnlyLibstdcxxStatic)
+ CmdArgs.push_back("-Bstatic");
+ ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+ if (OnlyLibstdcxxStatic)
+ CmdArgs.push_back("-Bdynamic");
+ }
+ CmdArgs.push_back("-lm");
+ }
+
+ // Silence warnings when linking C code with a C++ '-stdlib' argument.
+ Args.ClaimAllArgs(options::OPT_stdlib_EQ);
+
+ // Additional linker set-up and flags for Fortran. This is required in order
+ // to generate executables. As Fortran runtime depends on the C runtime,
+ // these dependencies need to be listed before the C runtime below (i.e.
+ // AddRunTimeLibs).
+ if (D.IsFlangMode() &&
+ !Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
+ tools::addFortranRuntimeLibraryPath(ToolChain, Args, CmdArgs);
+ tools::addFortranRuntimeLibs(ToolChain, Args, CmdArgs);
+ CmdArgs.push_back("-lm");
+ }
+
+ if (!Args.hasArg(options::OPT_nostdlib, options::OPT_r)) {
+ if (!Args.hasArg(options::OPT_nodefaultlibs)) {
+ if (IsStatic || IsStaticPIE)
+ CmdArgs.push_back("--start-group");
+
+ if (NeedsSanitizerDeps)
+ tools::linkSanitizerRuntimeDeps(ToolChain, Args, CmdArgs);
+
+ if (NeedsXRayDeps)
+ tools::linkXRayRuntimeDeps(ToolChain, Args, CmdArgs);
+
+ bool WantPthread = Args.hasArg(options::OPT_pthread) ||
+ Args.hasArg(options::OPT_pthreads);
+
+ // Use the static OpenMP runtime with -static-openmp
+ bool StaticOpenMP = Args.hasArg(options::OPT_static_openmp) &&
+ !Args.hasArg(options::OPT_static);
+
+ // FIXME: Only pass GompNeedsRT = true for platforms with libgomp that
+ // require librt. Most modern Linux platforms do, but some may not.
+ if (tools::addOpenMPRuntime(C, CmdArgs, ToolChain, Args, StaticOpenMP,
+ JA.isHostOffloading(Action::OFK_OpenMP),
+ /* GompNeedsRT= */ true))
+ // OpenMP runtimes implies pthreads when using the GNU toolchain.
+ // FIXME: Does this really make sense for all GNU toolchains?
+ WantPthread = true;
+
+ tools::AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+
+ if (WantPthread)
+ CmdArgs.push_back("-lpthread");
+
+ if (Args.hasArg(options::OPT_fsplit_stack))
+ CmdArgs.push_back("--wrap=pthread_create");
+
+ if (!Args.hasArg(options::OPT_nolibc))
+ CmdArgs.push_back("-lc");
+
+ // Cygwin specific
+ CmdArgs.push_back("-lcygwin");
+ CmdArgs.push_back("-ladvapi32");
+ CmdArgs.push_back("-lshell32");
+ CmdArgs.push_back("-luser32");
+ CmdArgs.push_back("-lkernel32");
+
+ // Add IAMCU specific libs, if needed.
+ if (IsIAMCU)
+ CmdArgs.push_back("-lgloss");
+
+ if (IsStatic || IsStaticPIE)
+ CmdArgs.push_back("--end-group");
+ else
+ tools::AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
+
+ // Add IAMCU specific libs (outside the group), if needed.
+ if (IsIAMCU) {
+ CmdArgs.push_back("--as-needed");
+ CmdArgs.push_back("-lsoftfp");
+ CmdArgs.push_back("--no-as-needed");
+ }
+ }
+
+ if (!Args.hasArg(options::OPT_nostartfiles) && !IsIAMCU) {
+ if (ToolChain.GetRuntimeLibType(Args) == ToolChain::RLT_CompilerRT) {
+ std::string crtend = ToolChain.getCompilerRT(Args, "crtend",
+ ToolChain::FT_Object);
+ if (ToolChain.getVFS().exists(crtend)) {
+ std::string P;
+ P = crtend;
+ CmdArgs.push_back(Args.MakeArgString(P));
+ }
+ }
+ CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crtend.o")));
+ }
+ }
+
+ Args.addAllArgs(CmdArgs, {options::OPT_T, options::OPT_t});
+
+ const char *Exec = Args.MakeArgString(ToolChain.GetLinkerPath());
+ C.addCommand(std::make_unique<Command>(JA, *this,
+ ResponseFileSupport::AtFileCurCP(),
+ Exec, CmdArgs, Inputs, Output));
+}
+
+auto Cygwin::buildLinker() const -> Tool * { return new cygwin::Linker(*this); }
diff --git a/clang/lib/Driver/ToolChains/Cygwin.h b/clang/lib/Driver/ToolChains/Cygwin.h
index d2f72c10c3b01..b76069fba6741 100644
--- a/clang/lib/Driver/ToolChains/Cygwin.h
+++ b/clang/lib/Driver/ToolChains/Cygwin.h
@@ -27,7 +27,28 @@ class LLVM_LIBRARY_VISIBILITY Cygwin : public Generic_GCC {
void
AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
llvm::opt::ArgStringList &CC1Args) const override;
+
+ const GCCInstallationDetector &
+ getGCCInstallation() const { return GCCInstallation; };
+
+protected:
+ Tool *buildLinker() const override;
+};
+
+namespace cygwin {
+class LLVM_LIBRARY_VISIBILITY Linker final : public Tool {
+public:
+ Linker(const ToolChain &TC) : Tool("cygwin::Linker", "linker", TC) {}
+
+ bool hasIntegratedCPP() const override { return false; }
+ bool isLinkJob() const override { return true; }
+
+ void ConstructJob(Compilation &C, const JobAction &JA,
+ const InputInfo &Output, const InputInfoList &Inputs,
+ const llvm::opt::ArgList &TCArgs,
+ const char *LinkingOutput) const override;
};
+} // end namespace cygwin
} // end namespace toolchains
} // end namespace driver
diff --git a/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/i686-pc-msys/10/crtend.o b/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/i686-pc-msys/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/x86_64-pc-cygwin/10/crtend.o b/clang/test/Driver/Inputs/basic_cross_cygwin_tree/usr/lib/gcc/x86_64-pc-cygwin/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/crt0.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/crt0.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/i686-pc-cygwin/10/crtend.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/i686-pc-cygwin/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/x86_64-pc-msys/10/crtend.o b/clang/test/Driver/Inputs/basic_cygwin_tree/usr/lib/gcc/x86_64-pc-msys/10/crtend.o
new file mode 100644
index 0000000000000..e69de29bb2d1d
diff --git a/clang/test/Driver/cygwin.cpp b/clang/test/Driver/cygwin.cpp
index dd75c48ddc6b3..8677e84c033fd 100644
--- a/clang/test/Driver/cygwin.cpp
+++ b/clang/test/Driver/cygwin.cpp
@@ -15,19 +15,19 @@
// CHECK-SAME: {{^}} "-internal-externc-isystem" "[[SYSROOT]]/usr/include/w32api"
// CHECK-SAME: "-femulated-tls"
// CHECK-SAME: "-exception-model=dwarf"
-// CHECK: "{{.*}}gcc{{(\.exe)?}}"
-// CHECK-SAME: "-m32"
+// CHECK: "{{.*}}ld{{(\.exe)?}}"
+// CHECK-SAME: "-m" "i386pe"
// RUN: %clang -### %s --target=i686-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: --stdlib=platform -static 2>&1 | FileCheck --check-prefix=CHECK-STATIC %s
// CHECK-STATIC: "-cc1" "-triple" "i686-pc-windows-cygnus"
// CHECK-STATIC-SAME: "-static-define"
-// CHECK-STATIC: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-STATIC: "{{.*}}ld{{(\.exe)?}}"
// CHECK-STATIC-SAME: "-static"
// RUN: %clang -### %s --target=i686-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: -shared 2>&1 | FileCheck --check-prefix=CHECK-SHARED %s
-// CHECK-SHARED: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-SHARED: "{{.*}}ld{{(\.exe)?}}"
// CHECK-SHARED-SAME: "-shared"
// RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
@@ -54,19 +54,19 @@
// CHECK-64-SAME: {{^}} "-internal-externc-isystem" "[[SYSROOT]]/usr/include/w32api"
// CHECK-64-SAME: "-femulated-tls"
// CHECK-64-SAME: "-exception-model=seh"
-// CHECK-64: "{{.*}}gcc{{(\.exe)?}}"
-// CHECK-64-SAME: "-m64"
+// CHECK-64: "{{.*}}ld{{(\.exe)?}}"
+// CHECK-64-SAME: "-m" "i386pep"
// RUN: %clang -### %s --target=x86_64-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: --stdlib=platform -static 2>&1 | FileCheck --check-prefix=CHECK-64-STATIC %s
// CHECK-64-STATIC: "-cc1" "-triple" "x86_64-pc-windows-cygnus"
// CHECK-64-STATIC-SAME: "-static-define"
-// CHECK-64-STATIC: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-64-STATIC: "{{.*}}ld{{(\.exe)?}}"
// CHECK-64-STATIC-SAME: "-static"
// RUN: %clang -### %s --target=x86_64-pc-cygwin --sysroot=%S/Inputs/basic_cygwin_tree \
// RUN: -shared 2>&1 | FileCheck --check-prefix=CHECK-64-SHARED %s
-// CHECK-64-SHARED: "{{.*}}gcc{{(\.exe)?}}"
+// CHECK-64-SHARED: "{{.*}}ld{{(\.exe)?}}"
// CHECK-64-SHARED-SAME: "-shared"
// RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
|
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
|
Thanks! This was on my mental TODO list but I haven't gotten back to looking at it. When I was thinking about this, I was thinking about modifying the MinGW linker with a couple of virtual functions and deriving from it for a Cygwin linker, to avoid so much code duplication. Maybe @mstorsjo can provide an opinion here? Also, the cygwin.cpp test was based on hurd.cpp, I'm thinking more of those tests are relevant now. |
jeremyd2019
reviewed
Jul 10, 2025
|
Oh, another proposed implementation to look at: #74933 I was planning to refer to that, MinGW.cpp, and the GCC spec for Cygwin, and see if I could come up with a couple of places where virtual functions could be added to the MinGW::Linker class so that Cygwin::Linker could derive from it and override (I think the "wrap" stuff and list of default libraries) |
kikairoya
reviewed
Jul 10, 2025
jeremyd2019
reviewed
Jul 10, 2025
|
Could you let I know output of Does this patch consider to use of LLD? ( gcc and clang can use with LLD:
+1 |
I meant just the Linker class. I don't think it's really possible to avoid a dedicated Cygwin driver, but I'm hoping it can keep close to the Generic_GCC base class rather than redoing so much stuff as MinGW did. |
Most of differences are related to triple, recognizing path, library names and linker options so many of them affects to Linker, so it will have amounts of virtual functions or StringRef members. |
I confirmed 'clang++ -fuse-ld=lld` works. What is your concern about LLD? |
|
Thanks. It looks like some linker options might still be missing or need adjustments:
Also, a few options should be handled in both
Here are a few issues I've seen when using LLD:
It would be great if this patch could be adjusted to support bootstrapping without requiring extra linker flags. |
|
If we should consider cross-compiling, it's needed to be aware that |
jeremyd2019
reviewed
Jul 11, 2025
I have been convinced by your points regarding However, as for |
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I was confused and not accurate earlier, sorry about that. Former, Latter, |
|
high-entropy-va would indeed break fork. I don't know about nxcompat. Here is a patch I had to lld to try to change defaults to match Cygwin defaults in BFD, but obviously it doesn't work out because lld can't tell if it's cygwin or mingw. I don't know if you want to try to handle all of these in the cygwin driver. It'd probably be the best place to do it since it does know that it is Cygwin and not MinGW. But it would mean that using gcc -fuse-ld=lld wouldn't work due to wrong defaults. |
I could not reproduce fork() failure even with high-entropy-va. Edited: Ah, if I run a.exe for many times, fork() sometimes fails. Thanks! |
...so that libc++, compiler-rt, and libunwind can be used by the options: -stdlib=libc++, -rtlib=compiler-rt, and -unwindlib=libunwind respectively. Along with this change, the test for this driver is also trimmed a bit. This is a follow-up patch to the commit 52924a2. Signed-off-by: Takashi Yano <[email protected]>
Added |
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...so that
libc++,compiler-rt, andlibunwindcan be used by the options:-stdlib=libc++,-rtlib=compiler-rt, and-unwindlib=libunwindrespectively. Along with this change, the test for this driver is also trimmed a bit.This is a followup patch for 52924a2.