diff --git a/docs/CommandGuide/clang.rst b/docs/CommandGuide/clang.rst
index 39dbe02a0b4381b121f92d9bb43749889f2b1fc6..9f6d6f588e5a4f06cde8a0e1aa496e8421dc9a65 100644
--- a/docs/CommandGuide/clang.rst
+++ b/docs/CommandGuide/clang.rst
@@ -257,6 +257,13 @@ Code Generation Options
Generate debug information. Note that Clang debug information works best at -O0.
+.. option:: -gmodules
+
+ Generate debug information that contains external references to
+ types defined in clang modules or precompiled headers instead of
+ emitting redundant debug type information into every object file.
+ This option implies `-fmodule-format=obj`.
+
.. option:: -fstandalone-debug -fno-standalone-debug
Clang supports a number of optimizations to reduce the size of debug
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 0417aa64a407662b2986b07a65d578f7650ddd1b..23134a6e39a39362689edbdc90d11263e7869dfa 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -167,6 +167,9 @@ def gnu_pubnames : Flag<["-"], "gnu-pubnames">,
HelpText<"Emit newer GNU style pubnames">;
def arange_sections : Flag<["-"], "arange_sections">,
HelpText<"Emit DWARF .debug_arange sections">;
+def dwarf_ext_refs : Flag<["-"], "dwarf-ext-refs">,
+ HelpText<"Generate debug info with external references to clang modules"
+ " or precompiled headers">;
def fforbid_guard_variables : Flag<["-"], "fforbid-guard-variables">,
HelpText<"Emit an error if a C++ static local initializer would need a guard variable">;
def no_implicit_float : Flag<["-"], "no-implicit-float">,
diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 271bf6e4388ad48a2065725cb592499618def14b..a2630fa891fe625c0d6ef895e6a28b9f64c5de42 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -1133,6 +1133,9 @@ def gno_column_info : Flag<["-"], "gno-column-info">, Group<g_flags_Group>;
def gsplit_dwarf : Flag<["-"], "gsplit-dwarf">, Group<g_flags_Group>;
def ggnu_pubnames : Flag<["-"], "ggnu-pubnames">, Group<g_flags_Group>;
def gdwarf_aranges : Flag<["-"], "gdwarf-aranges">, Group<g_flags_Group>;
+def gmodules : Flag <["-"], "gmodules">, Group<f_Group>,
+ HelpText<"Generate debug info with external references to clang modules"
+ " or precompiled headers">;
def headerpad__max__install__names : Joined<["-"], "headerpad_max_install_names">;
def help : Flag<["-", "--"], "help">, Flags<[CC1Option,CC1AsOption]>,
HelpText<"Display available options">;
diff --git a/include/clang/Frontend/ASTUnit.h b/include/clang/Frontend/ASTUnit.h
index abc824bbd2a471ed8979dff1beb5b14b6998b78d..f977bfdd78526381e0e9774db4df3559452f04a1 100644
--- a/include/clang/Frontend/ASTUnit.h
+++ b/include/clang/Frontend/ASTUnit.h
@@ -728,8 +728,8 @@ public:
static std::unique_ptr<ASTUnit> LoadFromASTFile(
const std::string &Filename, const PCHContainerReader &PCHContainerRdr,
IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
- const FileSystemOptions &FileSystemOpts, bool OnlyLocalDecls = false,
- ArrayRef<RemappedFile> RemappedFiles = None,
+ const FileSystemOptions &FileSystemOpts, bool UseDebugInfo = false,
+ bool OnlyLocalDecls = false, ArrayRef<RemappedFile> RemappedFiles = None,
bool CaptureDiagnostics = false, bool AllowPCHWithCompilerErrors = false,
bool UserFilesAreVolatile = false);
diff --git a/include/clang/Frontend/CodeGenOptions.def b/include/clang/Frontend/CodeGenOptions.def
index b5964eed73c34adaa2cd4174334e97726dbfee3f..fcfb953c24d18110105183f57e0fde8d460b851f 100644
--- a/include/clang/Frontend/CodeGenOptions.def
+++ b/include/clang/Frontend/CodeGenOptions.def
@@ -161,6 +161,9 @@ VALUE_CODEGENOPT(StackProbeSize , 32, 4096) ///< Overrides default stack
CODEGENOPT(DebugColumnInfo, 1, 0) ///< Whether or not to use column information
///< in debug info.
+CODEGENOPT(DebugTypeExtRefs, 1, 0) ///< Whether or not debug info should contain
+ ///< external references to a PCH or module.
+
CODEGENOPT(EmitLLVMUseLists, 1, 0) ///< Control whether to serialize use-lists.
/// The user specified number of registers to be used for integral arguments,
diff --git a/include/clang/Lex/HeaderSearchOptions.h b/include/clang/Lex/HeaderSearchOptions.h
index 94d0d258dee84913cf213c2588f6aa0d6e47d2bd..af4e7a1a3042331379907b218a2930712e018a91 100644
--- a/include/clang/Lex/HeaderSearchOptions.h
+++ b/include/clang/Lex/HeaderSearchOptions.h
@@ -169,7 +169,9 @@ public:
/// \brief Whether to validate system input files when a module is loaded.
unsigned ModulesValidateSystemHeaders : 1;
-public:
+ /// Whether the module includes debug information (-gmodules).
+ unsigned UseDebugInfo : 1;
+
HeaderSearchOptions(StringRef _Sysroot = "/")
: Sysroot(_Sysroot), ModuleFormat("raw"), DisableModuleHash(0),
ImplicitModuleMaps(0), ModuleMapFileHomeIsCwd(0),
@@ -178,7 +180,8 @@ public:
UseBuiltinIncludes(true), UseStandardSystemIncludes(true),
UseStandardCXXIncludes(true), UseLibcxx(false), Verbose(false),
ModulesValidateOncePerBuildSession(false),
- ModulesValidateSystemHeaders(false) {}
+ ModulesValidateSystemHeaders(false),
+ UseDebugInfo(false) {}
/// AddPath - Add the \p Path path to the specified \p Group list.
void AddPath(StringRef Path, frontend::IncludeDirGroup Group,
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index e09e57a231e84c60fba7da971199e2ac3c5c35e9..dd3f783cf4ee51f5534cf4f75e90a975c86a7bd9 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -45,6 +45,7 @@ using namespace clang::CodeGen;
CGDebugInfo::CGDebugInfo(CodeGenModule &CGM)
: CGM(CGM), DebugKind(CGM.getCodeGenOpts().getDebugInfo()),
+ DebugTypeExtRefs(CGM.getCodeGenOpts().DebugTypeExtRefs),
DBuilder(CGM.getModule()) {
CreateCompileUnit();
}
diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index 9c62f6c95411e621d89a8da7371a7c53fd1bd7a4..2ebd2cde71c41dd6fcff10c83030c68324ebe18d 100644
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -52,6 +52,7 @@ class CGDebugInfo {
friend class SaveAndRestoreLocation;
CodeGenModule &CGM;
const CodeGenOptions::DebugInfoKind DebugKind;
+ bool DebugTypeExtRefs;
llvm::DIBuilder DBuilder;
llvm::DICompileUnit *TheCU = nullptr;
SourceLocation CurLoc;
diff --git a/lib/CodeGen/ObjectFilePCHContainerOperations.cpp b/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
index 3611d9aa86f6b82db77ff779a21f7633599fe0b6..8342359b9ffc3fba7a8ede251cf22a146a8f558f 100644
--- a/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
+++ b/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
@@ -64,6 +64,7 @@ public:
// ThreadModel, but the backend expects them to be nonempty.
CodeGenOpts.CodeModel = "default";
CodeGenOpts.ThreadModel = "single";
+ CodeGenOpts.DebugTypeExtRefs = true;
CodeGenOpts.setDebugInfo(CodeGenOptions::FullDebugInfo);
CodeGenOpts.SplitDwarfFile = OutputFileName;
}
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 6de6eeb011c2f5ee4cf0ea4a9113b36bbad4de64..c90c63d850a4c0d8f677c12124aa0b7cc075b69b 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -3739,6 +3739,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
CmdArgs.push_back("-dwarf-column-info");
// FIXME: Move backend command line options to the module.
+ if (Args.hasArg(options::OPT_gmodules)) {
+ CmdArgs.push_back("-g");
+ CmdArgs.push_back("-dwarf-ext-refs");
+ CmdArgs.push_back("-fmodule-format=obj");
+ }
+
// -gsplit-dwarf should turn on -g and enable the backend dwarf
// splitting and extraction.
// FIXME: Currently only works on Linux.
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index 76a8cde8857c8264484ab9b85d7826abe20f61b8..90161af26cafe57147c14400bf214a25e7f8db2d 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -649,12 +649,12 @@ void ASTUnit::ConfigureDiags(IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
}
std::unique_ptr<ASTUnit> ASTUnit::LoadFromASTFile(
- const std::string &Filename,
- const PCHContainerReader &PCHContainerRdr,
+ const std::string &Filename, const PCHContainerReader &PCHContainerRdr,
IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
- const FileSystemOptions &FileSystemOpts, bool OnlyLocalDecls,
- ArrayRef<RemappedFile> RemappedFiles, bool CaptureDiagnostics,
- bool AllowPCHWithCompilerErrors, bool UserFilesAreVolatile) {
+ const FileSystemOptions &FileSystemOpts, bool UseDebugInfo,
+ bool OnlyLocalDecls, ArrayRef<RemappedFile> RemappedFiles,
+ bool CaptureDiagnostics, bool AllowPCHWithCompilerErrors,
+ bool UserFilesAreVolatile) {
std::unique_ptr<ASTUnit> AST(new ASTUnit(true));
// Recover resources if we crash before exiting this method.
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index f078b37c3c20604de1c25c81a51496e31136ff59..414e58939927a7740bf489581face68927066dd9 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -424,6 +424,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
Opts.DwarfVersion = 3;
else if (Args.hasArg(OPT_gdwarf_4))
Opts.DwarfVersion = 4;
+ Opts.DebugTypeExtRefs = Args.hasArg(OPT_dwarf_ext_refs);
if (const Arg *A =
Args.getLastArg(OPT_emit_llvm_uselists, OPT_no_emit_llvm_uselists))
diff --git a/lib/Frontend/FrontendAction.cpp b/lib/Frontend/FrontendAction.cpp
index 5b7494da58c03b9a178880e9271b96a2d4a9400e..149212290423de0a8a92842fa55f0cb82d2ab652 100644
--- a/lib/Frontend/FrontendAction.cpp
+++ b/lib/Frontend/FrontendAction.cpp
@@ -190,9 +190,9 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
- std::unique_ptr<ASTUnit> AST =
- ASTUnit::LoadFromASTFile(InputFile, CI.getPCHContainerReader(),
- Diags, CI.getFileSystemOpts());
+ std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
+ InputFile, CI.getPCHContainerReader(), Diags, CI.getFileSystemOpts(),
+ CI.getCodeGenOpts().DebugTypeExtRefs);
if (!AST)
goto failure;
diff --git a/lib/Lex/HeaderSearch.cpp b/lib/Lex/HeaderSearch.cpp
index dccedea64409ec93af1d4d474aee67074de79ac0..97e97954427d872a1db80c90a396d6687676463f 100644
--- a/lib/Lex/HeaderSearch.cpp
+++ b/lib/Lex/HeaderSearch.cpp
@@ -154,7 +154,7 @@ std::string HeaderSearch::getModuleFileName(StringRef ModuleName,
llvm::hash_code Hash =
llvm::hash_combine(DirName.lower(), FileName.lower(),
- HSOpts->ModuleFormat);
+ HSOpts->ModuleFormat, HSOpts->UseDebugInfo);
SmallString<128> HashStr;
llvm::APInt(64, size_t(Hash)).toStringUnsigned(HashStr, /*Radix*/36);
diff --git a/test/Driver/debug-options.c b/test/Driver/debug-options.c
index b55f2ccb66ccee97ecfe96ed59ffc62bfc3a5dd8..830305ad45dae6a0097059fe8efeb600335a97b6 100644
--- a/test/Driver/debug-options.c
+++ b/test/Driver/debug-options.c
@@ -77,6 +77,9 @@
//
// RUN: %clang -### -g %s 2>&1 | FileCheck -check-prefix=CI %s
//
+// RUN: %clang -### -gmodules %s 2>&1 \
+// RUN: | FileCheck -check-prefix=GEXTREFS %s
+//
// G: "-cc1"
// G: "-g"
//
@@ -126,3 +129,5 @@
// CI: "-dwarf-column-info"
//
// NOCI-NOT: "-dwarf-column-info"
+//
+// GEXTREFS: "-g" "-dwarf-ext-refs" "-fmodule-format=obj"
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 0334e721015dcf1b71b91b9e61d65f4b93abd23d..cbba64a431a409fe48d4b25c7ad3dfb6dfaf5669 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -2971,7 +2971,8 @@ enum CXErrorCode clang_createTranslationUnit2(CXIndex CIdx,
CompilerInstance::createDiagnostics(new DiagnosticOptions());
std::unique_ptr<ASTUnit> AU = ASTUnit::LoadFromASTFile(
ast_filename, CXXIdx->getPCHContainerOperations()->getRawReader(), Diags,
- FileSystemOpts, CXXIdx->getOnlyLocalDecls(), None,
+ FileSystemOpts, /*UseDebugInfo=*/false,
+ CXXIdx->getOnlyLocalDecls(), None,
/*CaptureDiagnostics=*/true,
/*AllowPCHWithCompilerErrors=*/true,
/*UserFilesAreVolatile=*/true);