r204417 - PR19215: When writing/reading a PCH that imported a module, store the location

[Aaron Ballman]

On Thu, Mar 20, 2014 at 8:33 PM, Richard Smith
<richard-llvm at metafoo.co.uk> wrote:
> Author: rsmith
> Date: Thu Mar 20 19:33:59 2014
> New Revision: 204417
>
> URL: http://llvm.org/viewvc/llvm-project?rev=204417&view=rev
> Log:
> PR19215: When writing/reading a PCH that imported a module, store the location
> at which that PCH imported each visible submodule of the module. Such locations
> are needed when synthesizing macro directives resulting from the import.
>
> Added:
>     cfe/trunk/test/Modules/Inputs/macro-undef-through-pch/
>     cfe/trunk/test/Modules/Inputs/macro-undef-through-pch/A.h
>     cfe/trunk/test/Modules/Inputs/macro-undef-through-pch/foo.h
>     cfe/trunk/test/Modules/Inputs/macro-undef-through-pch/module.map
>     cfe/trunk/test/Modules/macro-undef-through-pch.m
> Modified:
>     cfe/trunk/include/clang/Serialization/ASTReader.h
>     cfe/trunk/lib/Serialization/ASTReader.cpp
>     cfe/trunk/lib/Serialization/ASTWriter.cpp
>
> Modified: cfe/trunk/include/clang/Serialization/ASTReader.h
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Serialization/ASTReader.h?rev=204417&r1=204416&r2=204417&view=diff
> ==============================================================================
> --- cfe/trunk/include/clang/Serialization/ASTReader.h (original)
> +++ cfe/trunk/include/clang/Serialization/ASTReader.h Thu Mar 20 19:33:59 2014
> @@ -767,9 +767,14 @@ private:
>    // \brief A list of late parsed template function data.
>    SmallVector<uint64_t, 1> LateParsedTemplates;
>
> +  struct ImportedSubmodule {
> +    serialization::SubmoduleID ID;
> +    SourceLocation ImportLoc;
> +  };
> +
>    /// \brief A list of modules that were imported by precompiled headers or
>    /// any other non-module AST file.
> -  SmallVector<serialization::SubmoduleID, 2> ImportedModules;
> +  SmallVector<ImportedSubmodule, 2> ImportedModules;
>    //@}
>
>    /// \brief The directory that the PCH we are reading is stored in.
>
> Modified: cfe/trunk/lib/Serialization/ASTReader.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTReader.cpp?rev=204417&r1=204416&r2=204417&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Serialization/ASTReader.cpp (original)
> +++ cfe/trunk/lib/Serialization/ASTReader.cpp Thu Mar 20 19:33:59 2014
> @@ -1811,6 +1811,7 @@ void ASTReader::installImportedMacro(Ide
>      // Use the location at which the containing module file was first imported
>      // for now.
>      ImportLoc = MMI->F->DirectImportLoc;
> +    assert(ImportLoc.isValid() && "no import location for a visible macro?");
>    }
>
>    llvm::SmallVectorImpl<DefMacroDirective*> *Prev =
> @@ -3012,9 +3013,11 @@ bool ASTReader::ReadASTBlock(ModuleFile
>          // If we aren't loading a module (which has its own exports), make
>          // all of the imported modules visible.
>          // FIXME: Deal with macros-only imports.
> -        for (unsigned I = 0, N = Record.size(); I != N; ++I) {
> -          if (unsigned GlobalID = getGlobalSubmoduleID(F, Record[I]))
> -            ImportedModules.push_back(GlobalID);
> +        for (unsigned I = 0, N = Record.size(); I != N; /**/) {
> +          unsigned GlobalID = getGlobalSubmoduleID(F, Record[I++]);
> +          SourceLocation Loc = ReadSourceLocation(F, Record, I);
> +          if (GlobalID)
> +            ImportedModules.push_back({GlobalID, Loc});

Unfortunately, this construct doesn't work in MSVC 2012. I fixed up
similar usages in r204471. It does work in MSVC 2013, so eventually we
can use it instead of explicit constructors.

~Aaron