[flang] Search for #include "file" in right directory (take 2)

[klausler]

Summary

Make the #include "file" preprocessing directive begin its
search in the same directory as the file containing the directive,
as other preprocessors and our Fortran INCLUDE statement do.

Avoid current working directory for all source files except the original.

Resolve tests.

[kiranchandramohan]

flang/test/Flang-Driver/Inputs/basictestmoduleone.mod

1–5

I am guessing this version number (v1) might need to be updated with a change in module format. Is that expected to be rare since f18 uses the parser to parse the module file?

[awarzynski]

Thank you for re-submitting this so quickly @klausler !

These changes look good to me. I have one question about module files - is it safe to assume that modules with version information v1 are always going to be supported? I'm concerned that when we bump the version then we will also have to update the uploaded module files.

flang/test/Flang-Driver/include-module.f90

21

[nit] This and the line above are mutually exclusive, right? So this line could safely be deleted. Or replaced with:

! SINGLEINCLUDE:Source file 'basictestmoduletwo.mod' was not found

flang/include/flang/Parser/provenance.h

public:
   std::size_t size() const { return range_.size(); }
   const char &operator[](Provenance) const;
   Encoding encoding() const { return encoding_; }
   AllSources &set_encoding(Encoding e) {
     encoding_ = e;
     return *this;
   }
 
-  void PushSearchPathDirectory(std::string);
-  std::string PopSearchPathDirectory();
-  const SourceFile *Open(std::string path, llvm::raw_ostream &error);
+  void AppendSearchPathDirectory(std::string); // new last directory
+  const SourceFile *Open(std::string path, llvm::raw_ostream &error,
+      std::optional<std::string> &&prependPath = std::nullopt);
   const SourceFile *ReadStandardInput(llvm::raw_ostream &error);
 
   ProvenanceRange AddIncludedFile(
       const SourceFile &, ProvenanceRange, bool isModule = false);
   ProvenanceRange AddMacroCall(
       ProvenanceRange def, ProvenanceRange use, const std::string &expansion);
   ProvenanceRange AddCompilerInsertion(std::string);
 
private:
 
   const Origin &MapToOrigin(Provenance) const;
 
   // Elements are in ascending & contiguous order of .covers.
   std::vector<Origin> origin_;
   ProvenanceRange range_;
   std::map<char, Provenance> compilerInsertionProvenance_;
   std::vector<std::unique_ptr<SourceFile>> ownedSourceFiles_;
-  std::vector<std::string> searchPath_;
+  std::list<std::string> searchPath_;
   Encoding encoding_{Encoding::UTF_8};
 };
 
 // Represents the result of preprocessing and prescanning a single source
 // file (and all its inclusions) or module file.  Parsers operate within
 // single instances of CookedSource.
 class CookedSource {
 public:

flang/include/flang/Parser/source.h

 // Source file content is lightly normalized when the file is read.
 //  - Line ending markers are converted to single newline characters
 //  - A newline character is added to the last line of the file if one is needed
 //  - A Unicode byte order mark is recognized if present.
 
 #include "characters.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include <cstddef>
+#include <list>
+#include <optional>
 #include <string>
 #include <utility>
 #include <vector>
 
 namespace llvm {
 class raw_ostream;
 }
 
 namespace Fortran::parser {
 
 std::string DirectoryName(std::string path);
-std::string LocateSourceFile(
-    std::string name, const std::vector<std::string> &searchPath);
+std::optional<std::string> LocateSourceFile(
+    std::string name, const std::list<std::string> &searchPath);
 
 class SourceFile;
 
 struct SourcePosition {
   const SourceFile &file;
   int line, column;
 };
 

flang/lib/Frontend/FrontendActions.cpp

void InputOutputTestAction::ExecuteAction() {
   std::string buf;
   llvm::raw_string_ostream error_stream{buf};
   bool binaryMode = true;
 
   // Set/store input file info into CompilerInstance.
   CompilerInstance &ci = instance();
   Fortran::parser::AllSources &allSources{ci.allSources()};
   const Fortran::parser::SourceFile *sf;
-  sf = allSources.Open(path, error_stream);
+  sf = allSources.Open(path, error_stream, std::optional<std::string>{"."s});
   llvm::ArrayRef<char> fileContent = sf->content();
 
   // Output file descriptor to receive the content of input file.
   std::unique_ptr<llvm::raw_ostream> os;
 
   // Do not write on the output file if using outputStream_.
   if (ci.IsOutputStreamNull()) {
     os = ci.CreateDefaultOutputFile(

flang/lib/Parser/parsing.cpp

 Parsing::Parsing(AllCookedSources &allCooked) : allCooked_{allCooked} {}
 Parsing::~Parsing() {}
 
 const SourceFile *Parsing::Prescan(const std::string &path, Options options) {
   options_ = options;
   AllSources &allSources{allCooked_.allSources()};
   if (options.isModuleFile) {
     for (const auto &path : options.searchDirectories) {
-      allSources.PushSearchPathDirectory(path);
+      allSources.AppendSearchPathDirectory(path);
     }
   }
 
   std::string buf;
   llvm::raw_string_ostream fileError{buf};
   const SourceFile *sourceFile;
   if (path == "-") {
     sourceFile = allSources.ReadStandardInput(fileError);
   } else {
-    sourceFile = allSources.Open(path, fileError);
+    std::optional<std::string> currentDirectory{"."};
+    sourceFile = allSources.Open(path, fileError, std::move(currentDirectory));
   }
   if (!fileError.str().empty()) {
     ProvenanceRange range{allSources.AddCompilerInsertion(path)};
     messages_.Say(range, "%s"_err_en_US, fileError.str());
     return sourceFile;
   }
   CHECK(sourceFile);
 
   if (!options.isModuleFile) {
     // For .mod files we always want to look in the search directories.
-    // For normal source files we don't push them until after the primary
+    // For normal source files we don't add them until after the primary
     // source file has been opened.  If foo.f is missing from the current
     // working directory, we don't want to accidentally read another foo.f
     // from another directory that's on the search path.
     for (const auto &path : options.searchDirectories) {
-      allSources.PushSearchPathDirectory(path);
+      allSources.AppendSearchPathDirectory(path);
     }
   }
 
   Preprocessor preprocessor{allSources};
   for (const auto &predef : options.predefinitions) {
     if (predef.second) {
       preprocessor.Define(predef.first, *predef.second);
     } else {

flang/lib/Parser/preprocessor.cpp

 }
 
 void Preprocessor::Directive(const TokenSequence &dir, Prescanner *prescanner) {
   std::size_t tokens{dir.SizeInTokens()};
   std::size_t j{dir.SkipBlanks(0)};
   if (j == tokens) {
     return;
   }
+  CHECK(prescanner); // TODO: change to reference
   if (dir.TokenAt(j).ToString() != "#") {
     prescanner->Say(dir.GetTokenProvenanceRange(j), "missing '#'"_err_en_US);
     return;
   }
   j = dir.SkipBlanks(j + 1);
   while (tokens > 0 && dir.TokenAt(tokens - 1).IsBlank()) {
     --tokens;
   }
void Preprocessor::Directive(const TokenSequence &dir, Prescanner *prescanner) {
   } else if (dirName == "include") {
     if (j == tokens) {
       prescanner->Say(
           dir.GetIntervalProvenanceRange(dirOffset, tokens - dirOffset),
           "#include: missing name of file to include"_err_en_US);
       return;
     }
     std::string include;
+    std::optional<std::string> prependPath;
     if (dir.TokenAt(j).ToString() == "<") { // #include <foo>
       std::size_t k{j + 1};
       if (k >= tokens) {
         prescanner->Say(dir.GetIntervalProvenanceRange(j, tokens - j),
             "#include: file name missing"_err_en_US);
         return;
       }
       while (k < tokens && dir.TokenAt(k) != ">") {
         ++k;
       }
       if (k >= tokens) {
         prescanner->Say(dir.GetIntervalProvenanceRange(j, tokens - j),
             "#include: expected '>' at end of included file"_en_US);
       }
       TokenSequence braced{dir, j + 1, k - j - 1};
       include = ReplaceMacros(braced, *prescanner).ToString();
       j = k;
     } else if ((include = dir.TokenAt(j).ToString()).substr(0, 1) == "\"" &&
         include.substr(include.size() - 1, 1) == "\"") { // #include "foo"
       include = include.substr(1, include.size() - 2);
+      // #include "foo" starts search in directory of file containing
+      // the directive
+      auto prov{dir.GetTokenProvenanceRange(dirOffset).start()};
+      if (const auto *currentFile{allSources_.GetSourceFile(prov)}) {
+        prependPath = DirectoryName(currentFile->path());
+      }
     } else {
       prescanner->Say(dir.GetTokenProvenanceRange(j < tokens ? j : tokens - 1),
           "#include: expected name of file to include"_err_en_US);
       return;
     }
     if (include.empty()) {
       prescanner->Say(dir.GetTokenProvenanceRange(dirOffset),
           "#include: empty include file name"_err_en_US);
       return;
     }
     j = dir.SkipBlanks(j + 1);
     if (j < tokens && dir.TokenAt(j).ToString() != "!") {
       prescanner->Say(dir.GetIntervalProvenanceRange(j, tokens - j),
           "#include: extra stuff ignored after file name"_en_US);
     }
     std::string buf;
     llvm::raw_string_ostream error{buf};
-    const SourceFile *included{allSources_.Open(include, error)};
+    const SourceFile *included{
+        allSources_.Open(include, error, std::move(prependPath))};
     if (!included) {
       prescanner->Say(dir.GetTokenProvenanceRange(dirOffset),
           "#include: %s"_err_en_US, error.str());
     } else if (included->bytes() > 0) {
       ProvenanceRange fileRange{
           allSources_.AddIncludedFile(*included, dir.GetProvenanceRange())};
       Prescanner{*prescanner}
           .set_encoding(included->encoding())

flang/lib/Parser/prescan.cpp

if (*p != '\n' && *p != '!') {
     for (; *p != '\n' && *p != '!'; ++p) {
     }
     Say(GetProvenanceRange(garbage, p),
         "excess characters after path name"_en_US);
   }
   std::string buf;
   llvm::raw_string_ostream error{buf};
   Provenance provenance{GetProvenance(nextLine_)};
-  const SourceFile *currentFile{allSources_.GetSourceFile(provenance)};
-  if (currentFile) {
-    allSources_.PushSearchPathDirectory(DirectoryName(currentFile->path()));
-  }
-  const SourceFile *included{allSources_.Open(path, error)};
-  if (currentFile) {
-    allSources_.PopSearchPathDirectory();
+  std::optional<std::string> prependPath;
+  if (const SourceFile * currentFile{allSources_.GetSourceFile(provenance)}) {
+    prependPath = DirectoryName(currentFile->path());
   }
+  const SourceFile *included{
+      allSources_.Open(path, error, std::move(prependPath))};
   if (!included) {
     Say(provenance, "INCLUDE: %s"_err_en_US, error.str());
   } else if (included->bytes() > 0) {
     ProvenanceRange includeLineRange{
         provenance, static_cast<std::size_t>(p - nextLine_)};
     ProvenanceRange fileRange{
         allSources_.AddIncludedFile(*included, includeLineRange)};
     Prescanner{*this}.set_encoding(included->encoding()).Prescan(fileRange);

flang/lib/Parser/provenance.cpp

 
 AllSources::~AllSources() {}
 
 const char &AllSources::operator[](Provenance at) const {
   const Origin &origin{MapToOrigin(at)};
   return origin[origin.covers.MemberOffset(at)];
 }
 
-void AllSources::PushSearchPathDirectory(std::string directory) {
+void AllSources::AppendSearchPathDirectory(std::string directory) {
   // gfortran and ifort append to current path, PGI prepends
   searchPath_.push_back(directory);
 }
 
-std::string AllSources::PopSearchPathDirectory() {
-  std::string directory{searchPath_.back()};
-  searchPath_.pop_back();
-  return directory;
-}
-
-const SourceFile *AllSources::Open(std::string path, llvm::raw_ostream &error) {
+const SourceFile *AllSources::Open(std::string path, llvm::raw_ostream &error,
+    std::optional<std::string> &&prependPath) {
   std::unique_ptr<SourceFile> source{std::make_unique<SourceFile>(encoding_)};
-  if (source->Open(LocateSourceFile(path, searchPath_), error)) {
+  if (prependPath) {
+    // Set to "." for the initial source file; set to the directory name
+    // of the including file for #include "quoted-file" directives &
+    // INCLUDE statements.
+    searchPath_.emplace_front(std::move(*prependPath));
+  }
+  std::optional<std::string> found{LocateSourceFile(path, searchPath_)};
+  if (prependPath) {
+    searchPath_.pop_front();
+  }
+  if (!found) {
+    error << "Source file '" << path << "' was not found";
+    return nullptr;
+  } else if (source->Open(*found, error)) {
     return ownedSourceFiles_.emplace_back(std::move(source)).get();
   } else {
     return nullptr;
   }
 }
 
 const SourceFile *AllSources::ReadStandardInput(llvm::raw_ostream &error) {
   std::unique_ptr<SourceFile> source{std::make_unique<SourceFile>(encoding_)};

flang/lib/Parser/source.cpp

 }
 
 std::string DirectoryName(std::string path) {
   llvm::SmallString<128> pathBuf{path};
   llvm::sys::path::remove_filename(pathBuf);
   return pathBuf.str().str();
 }
 
-std::string LocateSourceFile(
-    std::string name, const std::vector<std::string> &searchPath) {
-  if (name.empty() || name == "-" || llvm::sys::path::is_absolute(name)) {
+std::optional<std::string> LocateSourceFile(
+    std::string name, const std::list<std::string> &searchPath) {
+  if (name == "-" || llvm::sys::path::is_absolute(name)) {
     return name;
   }
   for (const std::string &dir : searchPath) {
     llvm::SmallString<128> path{dir};
     llvm::sys::path::append(path, name);
     bool isDir{false};
     auto er = llvm::sys::fs::is_directory(path, isDir);
     if (!er && !isDir) {
       return path.str().str();
     }
   }
-  return name;
+  return std::nullopt;
 }
 
 std::size_t RemoveCarriageReturns(llvm::MutableArrayRef<char> buf) {
   std::size_t wrote{0};
   char *buffer{buf.data()};
   char *p{buf.data()};
   std::size_t bytes = buf.size();
   while (bytes > 0) {
bool SourceFile::Open(std::string path, llvm::raw_ostream &error) {
   buf_ = std::move(bufOr.get());
   ReadFile();
   return true;
 }
 
 bool SourceFile::ReadStandardInput(llvm::raw_ostream &error) {
   Close();
   path_ = "standard input";
-
   auto buf_or = llvm::MemoryBuffer::getSTDIN();
   if (!buf_or) {
     auto err = buf_or.getError();
     error << err.message();
     return false;
   }
   auto inbuf = std::move(buf_or.get());
   buf_ =
       llvm::WritableMemoryBuffer::getNewUninitMemBuffer(inbuf->getBufferSize());
   llvm::copy(inbuf->getBuffer(), buf_->getBufferStart());
   ReadFile();
   return true;
 }
 
 void SourceFile::ReadFile() {
   buf_end_ = RemoveCarriageReturns(buf_->getBuffer());
   if (content().size() == 0 || content().back() != '\n') {
     // Don't bother to copy if we have spare memory
     if (content().size() >= buf_->getBufferSize()) {
       auto tmp_buf{llvm::WritableMemoryBuffer::getNewUninitMemBuffer(
           content().size() + 1)};
       llvm::copy(content(), tmp_buf->getBufferStart());
-      Close();
       buf_ = std::move(tmp_buf);
     }
     buf_end_++;
     buf_->getBuffer()[buf_end_ - 1] = '\n';
   }
   IdentifyPayload();
   RecordLineStarts();
 }

flang/test/Flang-Driver/Inputs/basictestmoduleone.mod

-NOT A REAL MODULE FILE - USE THIS ONLY FOR TESTING THE DRIVER
+!mod$ v1 sum:1f5a35ada852dc66
+module basictestmoduleone
+type::t1
+end type
+end

flang/test/Flang-Driver/Inputs/module-dir/basictestmoduleone.mod

+!mod$ v1 sum:449b70509dd4bce3
+module basictestmoduleone
+type::t2
+end type
+end

flang/test/Flang-Driver/Inputs/module-dir/basictestmoduletwo.mod

-NOT A REAL MODULE FILE - USE THIS ONLY FOR TESTING THE DRIVER
+!mod$ v1 sum:563b9a1f049282d2
+module basictestmoduletwo
+end

flang/test/Flang-Driver/include-header.f90

 ! RUN: not %flang-new -fc1 -E %s  2>&1 | FileCheck %s --check-prefix=UNINCLUDED
 ! RUN: %flang-new -fc1 -E -I %S/Inputs %s  2>&1 | FileCheck %s --check-prefix=SINGLEINCLUDE
 ! RUN: %flang-new -fc1 -E -I %S/Inputs -I %S/Inputs/header-dir %s  2>&1 | FileCheck %s --check-prefix=MAINDIRECTORY
 ! RUN: %flang-new -fc1 -E -I %S/Inputs/header-dir -I %S/Inputs %s  2>&1 | FileCheck %s --check-prefix=SUBDIRECTORY
 
 !--------------------------------------------
 ! EXPECTED OUTPUT FOR MISSING INCLUDED FILE
 !--------------------------------------------
-! UNINCLUDED:No such file or directory
+! UNINCLUDED:#include: Source file 'basic-header-one.h' was not found
 ! UNINCLUDED-NOT:program b
 ! UNINCLUDED-NOT:program c
 
 !---------------------------------------------
 ! EXPECTED OUTPUT FOR A SINGLE INCLUDED FOLDER
 !--------------------------------------------
 ! SINGLEINCLUDE:program maindirectoryone
 ! SINGLEINCLUDE-NOT:program x

flang/test/Flang-Driver/include-module.f90

 ! Ensure argument -I works as expected with module files.
-! The module files for this test are not real module files.
 
 ! REQUIRES: new-flang-driver
 
 !--------------------------
 ! FLANG DRIVER (flang-new)
 !--------------------------
 ! RUN: not %flang-new -fsyntax-only -I %S/Inputs -I %S/Inputs/module-dir %s  2>&1 | FileCheck %s --check-prefix=INCLUDED
 ! RUN: not %flang-new -fsyntax-only -I %S/Inputs %s  2>&1 | FileCheck %s --check-prefix=SINGLEINCLUDE
 
 !-----------------------------------------
 ! FRONTEND FLANG DRIVER (flang-new -fc1)
 !-----------------------------------------
 ! RUN: not %flang-new -fc1 -fsyntax-only -I %S/Inputs -I %S/Inputs/module-dir %s  2>&1 | FileCheck %s --check-prefix=INCLUDED
 ! RUN: not %flang-new -fc1 -fsyntax-only -I %S/Inputs %s  2>&1 | FileCheck %s --check-prefix=SINGLEINCLUDE
 
 !-----------------------------------------
 ! EXPECTED OUTPUT FOR MISSING MODULE FILE
 !-----------------------------------------
-! SINGLEINCLUDE:No such file or directory
+! SINGLEINCLUDE:Error reading module file for module 'basictestmoduletwo'
 ! SINGLEINCLUDE-NOT:Error reading module file for module 'basictestmoduletwo'
+! SINGLEINCLUDE-NOT:error: Derived type 't1' not found
+! SINGLEINCLUDE:error: Derived type 't2' not found
 
 !---------------------------------------
 ! EXPECTED OUTPUT FOR ALL MODULES FOUND
 !---------------------------------------
-! INCLUDED-NOT:No such file or directory
+! INCLUDED-NOT:Error reading module file
+! INCLUDED-NOT:error: Derived type 't1' not found
+! INCLUDED:error: Derived type 't2' not found
 
 program test_dash_I_with_mod_files
     USE basictestmoduleone
     USE basictestmoduletwo
+    type(t1) :: x1 ! t1 defined in Inputs/basictestmoduleone.mod
+    type(t2) :: x2 ! t2 defined in Inputs/module-dir/basictestmoduleone.mod
 end

flang/tools/f18/f18.cpp

struct GetDefinitionArgs {
   int line, startColumn, endColumn;
 };
 
 struct DriverOptions {
   DriverOptions() {}
   bool verbose{false}; // -v
   bool compileOnly{false}; // -c
   std::string outputPath; // -o path
-  std::vector<std::string> searchDirectories{"."s}; // -I dir
+  std::vector<std::string> searchDirectories; // -I dir
   std::string moduleDirectory{"."s}; // -module dir
   std::string moduleFileSuffix{".mod"}; // -moduleSuffix suff
   bool forcedForm{false}; // -Mfixed or -Mfree appeared
   bool warnOnNonstandardUsage{false}; // -Mstandard
   bool warningsAreErrors{false}; // -Werror
   bool byteswapio{false}; // -byteswapio
   Fortran::parser::Encoding encoding{Fortran::parser::Encoding::UTF_8};
   bool parseOnly{false};

flang/unittests/Frontend/FrontendActionTest.cpp

TEST_F(FrontendActionTest, ParseSyntaxOnly) {
   // Execute the action.
   bool success = ExecuteCompilerInvocation(&compInst_);
 
   // Validate the expected output.
   EXPECT_FALSE(success);
   EXPECT_TRUE(!outputDiagBuffer.empty());
   EXPECT_TRUE(
       llvm::StringRef(outputDiagBuffer.data())
-          .startswith(
+          .contains(
               ":1:14: error: IF statement is not allowed in IF statement\n"));
 }
 } // namespace