From: Eli Friedman Date: Wed, 2 Nov 2011 01:53:16 +0000 (+0000) Subject: Add an option to emulate the strange Apple gcc behavior of #pragma pack. X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=19bda3ad8b5d37e505214e82fab1d0a0bf00f0fd;p=clang Add an option to emulate the strange Apple gcc behavior of #pragma pack. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143527 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/clang/Basic/LangOptions.def b/include/clang/Basic/LangOptions.def index 03882f8cdb..5cf40ec578 100644 --- a/include/clang/Basic/LangOptions.def +++ b/include/clang/Basic/LangOptions.def @@ -150,6 +150,8 @@ BENIGN_LANGOPT(NumLargeByValueCopy, 32, 0, VALUE_LANGOPT(MSCVersion, 32, 0, "version of Microsoft Visual C/C++") +LANGOPT(ApplePragmaPack, 1, 0, "Apple gcc-compatible #pragma pack handling") + #undef LANGOPT #undef VALUE_LANGOPT #undef BENIGN_LANGOPT diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td index 1a6008e779..bfcdc935e8 100644 --- a/include/clang/Driver/CC1Options.td +++ b/include/clang/Driver/CC1Options.td @@ -608,6 +608,8 @@ def fdeprecated_macro : Flag<"-fdeprecated-macro">, HelpText<"Defines the __DEPRECATED macro">; def fno_deprecated_macro : Flag<"-fno-deprecated-macro">, HelpText<"Undefines the __DEPRECATED macro">; +def fapple_pragma_pack : Flag<"-fapple-pragma-pack">, + HelpText<"Enable Apple gcc-compatible #pragma pack handling">; //===----------------------------------------------------------------------===// // Header Search Options diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td index fea6e4fd45..40a814ee75 100644 --- a/include/clang/Driver/Options.td +++ b/include/clang/Driver/Options.td @@ -261,6 +261,7 @@ def fno_PIE : Flag<"-fno-PIE">, Group, Flags<[NoArgumentUnused]>; def faccess_control : Flag<"-faccess-control">, Group; def fallow_unsupported : Flag<"-fallow-unsupported">, Group; def fapple_kext : Flag<"-fapple-kext">, Group; +def fapple_pragma_pack : Flag<"-fapple-pragma-pack">, Group; def fasm : Flag<"-fasm">, Group; def fasm_blocks : Flag<"-fasm-blocks">, Group; @@ -355,6 +356,7 @@ def fmudflap : Flag<"-fmudflap">, Group; def fnested_functions : Flag<"-fnested-functions">, Group; def fnext_runtime : Flag<"-fnext-runtime">, Group; def fno_access_control : Flag<"-fno-access-control">, Group; +def fno_apple_pragma_pack : Flag<"-fno-apple-pragma-pack">, Group; def fno_asm : Flag<"-fno-asm">, Group; def fno_asynchronous_unwind_tables : Flag<"-fno-asynchronous-unwind-tables">, Group; def fno_assume_sane_operator_new : Flag<"-fno-assume-sane-operator-new">, Group; diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp index 4db6d007fc..1a8c2e834c 100644 --- a/lib/Driver/Tools.cpp +++ b/lib/Driver/Tools.cpp @@ -2171,6 +2171,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA, D.Diag(diag::warn_drv_clang_unsupported) << A->getAsString(Args); } + if (Args.hasFlag(options::OPT_fapple_pragma_pack, + options::OPT_fno_apple_pragma_pack, false)) + CmdArgs.push_back("-fapple-pragma-pack"); + // Default to -fno-builtin-str{cat,cpy} on Darwin for ARM. // // FIXME: This is disabled until clang -cc1 supports -fno-builtin-foo. PR4941. diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp index 79e087e943..34ad608475 100644 --- a/lib/Frontend/CompilerInvocation.cpp +++ b/lib/Frontend/CompilerInvocation.cpp @@ -777,6 +777,8 @@ static void LangOptsToArgs(const LangOptions &Opts, Res.push_back("-fdelayed-template-parsing"); if (Opts.Deprecated) Res.push_back("-fdeprecated-macro"); + if (Opts.ApplePragmaPack) + Res.push_back("-fapple-pragma-pack"); } static void PreprocessorOptsToArgs(const PreprocessorOptions &Opts, @@ -1763,6 +1765,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK, Opts.FakeAddressSpaceMap = Args.hasArg(OPT_ffake_address_space_map); Opts.ParseUnknownAnytype = Args.hasArg(OPT_funknown_anytype); Opts.DebuggerSupport = Args.hasArg(OPT_fdebugger_support); + Opts.ApplePragmaPack = Args.hasArg(OPT_fapple_pragma_pack); // Record whether the __DEPRECATED define was requested. Opts.Deprecated = Args.hasFlag(OPT_fdeprecated_macro, diff --git a/lib/Parse/ParsePragma.cpp b/lib/Parse/ParsePragma.cpp index 2ccb6ea88d..2069d31dd2 100644 --- a/lib/Parse/ParsePragma.cpp +++ b/lib/Parse/ParsePragma.cpp @@ -110,6 +110,12 @@ void PragmaPackHandler::HandlePragma(Preprocessor &PP, return; PP.Lex(Tok); + + // In MSVC/gcc, #pragma pack(4) sets the alignment without affecting + // the push/pop stack. + // In Apple gcc, #pragma pack(4) is equivalent to #pragma pack(push, 4) + if (PP.getLangOptions().ApplePragmaPack) + Kind = Sema::PPK_Push; } else if (Tok.is(tok::identifier)) { const IdentifierInfo *II = Tok.getIdentifierInfo(); if (II->isStr("show")) { @@ -159,6 +165,11 @@ void PragmaPackHandler::HandlePragma(Preprocessor &PP, } } } + } else if (PP.getLangOptions().ApplePragmaPack) { + // In MSVC/gcc, #pragma pack() resets the alignment without affecting + // the push/pop stack. + // In Apple gcc #pragma pack() is equivalent to #pragma pack(pop). + Kind = Sema::PPK_Pop; } if (Tok.isNot(tok::r_paren)) { diff --git a/test/Sema/pragma-pack-apple.c b/test/Sema/pragma-pack-apple.c new file mode 100644 index 0000000000..5b33c03c38 --- /dev/null +++ b/test/Sema/pragma-pack-apple.c @@ -0,0 +1,10 @@ +// RUN: %clang -fsyntax-only %s 2>&1 | FileCheck %s +// RUN: %clang -fsyntax-only -fapple-pragma-pack %s 2>&1 | FileCheck -check-prefix=CHECK-APPLE %s + +#pragma pack(push,1) +#pragma pack(2) +#pragma pack() +#pragma pack(show) + +// CHECK: pack(show) == 8 +// CHECK-APPLE: pack(show) == 1