From c542d379958d1e44744aa9474f79c6732264121d Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Fri, 27 Jun 2014 17:02:02 +0000 Subject: [PATCH] clang-cl: Map /EHs- to -fno-exceptions This isn't 100% compatible with MSVC, but it's close enough. MSVC's /EH flag doesn't really control exceptions so much as how to clean up after an exception is thrown. The upshot is that cl.exe /EHs- will compile try, throw, and catch statements with a warning, but clang-cl will reject such constructs with a hard error. We can't compile such EH constructs anyway, but this may matter to consumers of the AST. Reviewers: hans Differential Revision: http://reviews.llvm.org/D4317 llvm-svn: 211909 --- clang/include/clang/Driver/CLCompatOptions.td | 2 +- clang/lib/Driver/Tools.cpp | 56 +++++++++++++++++++++++++-- clang/test/Driver/cl-eh.cpp | 24 ++++++++++++ clang/test/Driver/cl-fallback.c | 4 +- 4 files changed, 80 insertions(+), 6 deletions(-) create mode 100644 clang/test/Driver/cl-eh.cpp diff --git a/clang/include/clang/Driver/CLCompatOptions.td b/clang/include/clang/Driver/CLCompatOptions.td index 13456b9..66d4242 100644 --- a/clang/include/clang/Driver/CLCompatOptions.td +++ b/clang/include/clang/Driver/CLCompatOptions.td @@ -140,6 +140,7 @@ def _SLASH_Zs : CLFlag<"Zs">, HelpText<"Syntax-check only">, def _SLASH_M_Group : OptionGroup<"">, Group; +def _SLASH_EH : CLJoined<"EH">, HelpText<"Exception handling model">; def _SLASH_EP : CLFlag<"EP">, HelpText<"Disable linemarker output and preprocess to stdout">; def _SLASH_FA : CLFlag<"FA">, @@ -209,7 +210,6 @@ def _SLASH_bigobj : CLFlag<"bigobj">; def _SLASH_clr : CLJoined<"clr">; def _SLASH_d2Zi_PLUS : CLFlag<"d2Zi+">; def _SLASH_doc : CLJoined<"doc">; -def _SLASH_EH : CLJoined<"EH">; def _SLASH_FA_joined : CLJoined<"FA">; def _SLASH_favor : CLJoined<"favor">; def _SLASH_FC : CLFlag<"FC">; diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp index 835606c..06c6810 100644 --- a/clang/lib/Driver/Tools.cpp +++ b/clang/lib/Driver/Tools.cpp @@ -3846,9 +3846,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA, } } - // Add exception args. - addExceptionArgs(Args, InputType, getToolChain().getTriple(), - KernelOrKext, objcRuntime, CmdArgs); + // Handle GCC-style exception args. + if (!C.getDriver().IsCLMode()) + addExceptionArgs(Args, InputType, getToolChain().getTriple(), KernelOrKext, + objcRuntime, CmdArgs); if (getToolChain().UseSjLjExceptions()) CmdArgs.push_back("-fsjlj-exceptions"); @@ -4352,6 +4353,45 @@ ObjCRuntime Clang::AddObjCRuntimeArgs(const ArgList &args, return runtime; } +static bool maybeConsumeDash(const std::string &EH, size_t &I) { + bool HaveDash = (I + 1 < EH.size() && EH[I + 1] == '-'); + I += HaveDash; + return !HaveDash; +}; + +struct EHFlags { + EHFlags() : Synch(false), Asynch(false), NoExceptC(false) {} + bool Synch; + bool Asynch; + bool NoExceptC; +}; + +/// /EH controls whether to run destructor cleanups when exceptions are +/// thrown. There are three modifiers: +/// - s: Cleanup after "synchronous" exceptions, aka C++ exceptions. +/// - a: Cleanup after "asynchronous" exceptions, aka structured exceptions. +/// The 'a' modifier is unimplemented and fundamentally hard in LLVM IR. +/// - c: Assume that extern "C" functions are implicitly noexcept. This +/// modifier is an optimization, so we ignore it for now. +/// The default is /EHs-c-, meaning cleanups are disabled. +static EHFlags parseClangCLEHFlags(const Driver &D, const ArgList &Args) { + EHFlags EH; + std::vector EHArgs = Args.getAllArgValues(options::OPT__SLASH_EH); + for (auto EHVal : EHArgs) { + for (size_t I = 0, E = EHVal.size(); I != E; ++I) { + switch (EHVal[I]) { + case 'a': EH.Asynch = maybeConsumeDash(EHVal, I); continue; + case 'c': EH.NoExceptC = maybeConsumeDash(EHVal, I); continue; + case 's': EH.Synch = maybeConsumeDash(EHVal, I); continue; + default: break; + } + D.Diag(clang::diag::err_drv_invalid_value) << "/EH" << EHVal; + break; + } + } + return EH; +} + void Clang::AddClangCLArgs(const ArgList &Args, ArgStringList &CmdArgs) const { unsigned RTOptionID = options::OPT__SLASH_MT; @@ -4404,13 +4444,20 @@ void Clang::AddClangCLArgs(const ArgList &Args, ArgStringList &CmdArgs) const { if (!Args.hasArg(options::OPT_frtti, options::OPT_fno_rtti)) CmdArgs.push_back("-fno-rtti"); + const Driver &D = getToolChain().getDriver(); + EHFlags EH = parseClangCLEHFlags(D, Args); + // FIXME: Do something with NoExceptC. + if (EH.Synch || EH.Asynch) { + CmdArgs.push_back("-fexceptions"); + CmdArgs.push_back("-fcxx-exceptions"); + } + // /EP should expand to -E -P. if (Args.hasArg(options::OPT__SLASH_EP)) { CmdArgs.push_back("-E"); CmdArgs.push_back("-P"); } - const Driver &D = getToolChain().getDriver(); Arg *MostGeneralArg = Args.getLastArg(options::OPT__SLASH_vmg); Arg *BestCaseArg = Args.getLastArg(options::OPT__SLASH_vmb); if (MostGeneralArg && BestCaseArg) @@ -7692,6 +7739,7 @@ Command *visualstudio::Compile::GetCommand(Compilation &C, const JobAction &JA, // Flags that can simply be passed through. Args.AddAllArgs(CmdArgs, options::OPT__SLASH_LD); Args.AddAllArgs(CmdArgs, options::OPT__SLASH_LDd); + Args.AddAllArgs(CmdArgs, options::OPT__SLASH_EH); // The order of these flags is relevant, so pick the last one. if (Arg *A = Args.getLastArg(options::OPT__SLASH_MD, options::OPT__SLASH_MDd, diff --git a/clang/test/Driver/cl-eh.cpp b/clang/test/Driver/cl-eh.cpp new file mode 100644 index 0000000..8a3450a --- /dev/null +++ b/clang/test/Driver/cl-eh.cpp @@ -0,0 +1,24 @@ +// Don't attempt slash switches on msys bash. +// REQUIRES: shell-preserves-root + +// Note: %s must be preceded by --, otherwise it may be interpreted as a +// command-line option, e.g. on Mac where %s is commonly under /Users. + +// RUN: %clang_cl /c /EHsc -### -- %s 2>&1 | FileCheck -check-prefix=EHsc %s +// EHsc: "-fexceptions" + +// RUN: %clang_cl /c /EHs-c- -### -- %s 2>&1 | FileCheck -check-prefix=EHs_c_ %s +// EHs_c_-NOT: "-fexceptions" + +// RUN: %clang_cl /c /EHs- /EHc- -### -- %s 2>&1 | FileCheck -check-prefix=EHs_EHc_ %s +// EHs_EHc_-NOT: "-fexceptions" + +// RUN: %clang_cl /c /EHs- /EHs -### -- %s 2>&1 | FileCheck -check-prefix=EHs_EHs %s +// EHs_EHs: "-fexceptions" + +// RUN: %clang_cl /c /EHs- /EHsa -### -- %s 2>&1 | FileCheck -check-prefix=EHs_EHa %s +// EHs_EHa: "-fexceptions" + +// RUN: %clang_cl /c /EHinvalid -### -- %s 2>&1 | FileCheck -check-prefix=EHinvalid %s +// EHinvalid: error: invalid value 'invalid' in '/EH' +// EHinvalid-NOT: error: diff --git a/clang/test/Driver/cl-fallback.c b/clang/test/Driver/cl-fallback.c index 1bb0993..99cf627 100644 --- a/clang/test/Driver/cl-fallback.c +++ b/clang/test/Driver/cl-fallback.c @@ -5,7 +5,7 @@ // command-line option, e.g. on Mac where %s is commonly under /Users. // RUN: %clang_cl /fallback /Dfoo=bar /Ubaz /Ifoo /O0 /Ox /GR /GR- /Gy /Gy- \ -// RUN: /Gw /Gw- /LD /LDd /MD /MDd /MTd /MT /FImyheader.h /Zi \ +// RUN: /Gw /Gw- /LD /LDd /EHs /EHs- /MD /MDd /MTd /MT /FImyheader.h /Zi \ // RUN: -### -- %s 2>&1 \ // RUN: | FileCheck %s // CHECK: "-fdiagnostics-format" "msvc-fallback" @@ -25,6 +25,8 @@ // CHECK: "/FImyheader.h" // CHECK: "/LD" // CHECK: "/LDd" +// CHECK: "/EHs" +// CHECK: "/EHs-" // CHECK: "/MT" // CHECK: "/Tc" "{{.*cl-fallback.c}}" // CHECK: "/Fo{{.*cl-fallback.*.obj}}" -- 2.7.4