Index: cfe/trunk/include/clang/Driver/Options.td =================================================================== --- cfe/trunk/include/clang/Driver/Options.td +++ cfe/trunk/include/clang/Driver/Options.td @@ -1384,6 +1384,10 @@ def fno_pic : Flag<["-"], "fno-pic">, Group; def fpie : Flag<["-"], "fpie">, Group; def fno_pie : Flag<["-"], "fno-pie">, Group; +def fplt : Flag<["-"], "fplt">, Group, Flags<[CC1Option]>, + HelpText<"Use the PLT to make function calls">; +def fno_plt : Flag<["-"], "fno-plt">, Group, Flags<[CC1Option]>, + HelpText<"Do not use the PLT to make function calls">; def fropi : Flag<["-"], "fropi">, Group; def fno_ropi : Flag<["-"], "fno-ropi">, Group; def frwpi : Flag<["-"], "frwpi">, Group; Index: cfe/trunk/include/clang/Frontend/CodeGenOptions.def =================================================================== --- cfe/trunk/include/clang/Frontend/CodeGenOptions.def +++ cfe/trunk/include/clang/Frontend/CodeGenOptions.def @@ -297,6 +297,8 @@ /// Whether to emit .debug_gnu_pubnames section instead of .debug_pubnames. CODEGENOPT(GnuPubnames, 1, 0) +CODEGENOPT(NoPLT, 1, 0) + #undef CODEGENOPT #undef ENUM_CODEGENOPT #undef VALUE_CODEGENOPT Index: cfe/trunk/lib/CodeGen/CGCall.cpp =================================================================== --- cfe/trunk/lib/CodeGen/CGCall.cpp +++ cfe/trunk/lib/CodeGen/CGCall.cpp @@ -1855,6 +1855,16 @@ !(TargetDecl && TargetDecl->hasAttr())) FuncAttrs.addAttribute("split-stack"); + // Add NonLazyBind attribute to function declarations when -fno-plt + // is used. + if (TargetDecl && CodeGenOpts.NoPLT) { + if (auto *Fn = dyn_cast(TargetDecl)) { + if (!Fn->isDefined() && !AttrOnCallSite) { + FuncAttrs.addAttribute(llvm::Attribute::NonLazyBind); + } + } + } + if (!AttrOnCallSite) { bool DisableTailCalls = CodeGenOpts.DisableTailCalls || Index: cfe/trunk/lib/Driver/ToolChains/Clang.cpp =================================================================== --- cfe/trunk/lib/Driver/ToolChains/Clang.cpp +++ cfe/trunk/lib/Driver/ToolChains/Clang.cpp @@ -3423,6 +3423,10 @@ CmdArgs.push_back("-mpie-copy-relocations"); } + if (Args.hasFlag(options::OPT_fno_plt, options::OPT_fplt, false)) { + CmdArgs.push_back("-fno-plt"); + } + // -fhosted is default. // TODO: Audit uses of KernelOrKext and see where it'd be more appropriate to // use Freestanding. Index: cfe/trunk/lib/Frontend/CompilerInvocation.cpp =================================================================== --- cfe/trunk/lib/Frontend/CompilerInvocation.cpp +++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp @@ -653,6 +653,7 @@ Args.hasArg(OPT_mincremental_linker_compatible); Opts.PIECopyRelocations = Args.hasArg(OPT_mpie_copy_relocations); + Opts.NoPLT = Args.hasArg(OPT_fno_plt); Opts.OmitLeafFramePointer = Args.hasArg(OPT_momit_leaf_frame_pointer); Opts.SaveTempLabels = Args.hasArg(OPT_msave_temp_labels); Opts.NoDwarfDirectoryAsm = Args.hasArg(OPT_fno_dwarf_directory_asm); Index: cfe/trunk/test/CodeGen/noplt.c =================================================================== --- cfe/trunk/test/CodeGen/noplt.c +++ cfe/trunk/test/CodeGen/noplt.c @@ -0,0 +1,9 @@ +// RUN: %clang_cc1 -emit-llvm -fno-plt %s -o - | FileCheck %s -check-prefix=CHECK-NOPLT + +// CHECK-NOPLT: Function Attrs: nonlazybind +// CHECK-NOPLT-NEXT: declare i32 @foo +int foo(); + +int bar() { + return foo(); +}