Implement checking for macro definitions that occur on the command
line when using a PCH that were not provided when building the PCH
file. If those names were used as identifiers somewhere in the PCH
file, reject the PCH file.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70321 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticFrontendKinds.td b/include/clang/Basic/DiagnosticFrontendKinds.td
index 2c5dfcc..4ed49a0 100644
--- a/include/clang/Basic/DiagnosticFrontendKinds.td
+++ b/include/clang/Basic/DiagnosticFrontendKinds.td
@@ -123,5 +123,7 @@
"macro definitions used to build the precompiled header are missing">;
def note_using_macro_def_from_pch : Note<
"using this macro definition from precompiled header">;
-
+def warn_macro_name_used_in_pch : Warning<
+ "definition of macro %0 conflicts with an identifier used in the "
+ "precompiled header">;
}
diff --git a/include/clang/Frontend/PCHReader.h b/include/clang/Frontend/PCHReader.h
index 907ab7e..cd23cac 100644
--- a/include/clang/Frontend/PCHReader.h
+++ b/include/clang/Frontend/PCHReader.h
@@ -280,6 +280,16 @@
/// Objective-C protocols.
llvm::SmallVector<Decl *, 16> InterestingDecls;
+ /// \brief The file ID for the predefines buffer in the PCH file.
+ FileID PCHPredefinesBufferID;
+
+ /// \brief Pointer to the beginning of the predefines buffer in the
+ /// PCH file.
+ const char *PCHPredefines;
+
+ /// \brief Length of the predefines buffer in the PCH file.
+ unsigned PCHPredefinesLen;
+
/// \brief Suggested contents of the predefines buffer, after this
/// PCH file has been processed.
///
diff --git a/lib/Frontend/PCHReader.cpp b/lib/Frontend/PCHReader.cpp
index f1d7e7a..e7404f8 100644
--- a/lib/Frontend/PCHReader.cpp
+++ b/lib/Frontend/PCHReader.cpp
@@ -507,9 +507,17 @@
std::string MacroName = Extra.substr(StartOfMacroName,
EndOfMacroName - StartOfMacroName);
- // FIXME: Perform this check!
- fprintf(stderr, "FIXME: check whether '%s' was used in the PCH file\n",
- MacroName.c_str());
+ // Check whether this name was used somewhere in the PCH file. If
+ // so, defining it as a macro could change behavior, so we reject
+ // the PCH file.
+ if (IdentifierInfo *II = get(MacroName.c_str(),
+ MacroName.c_str() + MacroName.size())) {
+ Diag(diag::warn_macro_name_used_in_pch)
+ << II;
+ Diag(diag::note_ignoring_pch)
+ << FileName;
+ return true;
+ }
// Add this definition to the suggested predefines buffer.
SuggestedPredefines += Extra;
@@ -818,9 +826,11 @@
Name);
FileID BufferID = SourceMgr.createFileIDForMemBuffer(Buffer, ID, Offset);
- if (strcmp(Name, "<built-in>") == 0
- && CheckPredefinesBuffer(BlobStart, BlobLen - 1, BufferID))
- return IgnorePCH;
+ if (strcmp(Name, "<built-in>") == 0) {
+ PCHPredefinesBufferID = BufferID;
+ PCHPredefines = BlobStart;
+ PCHPredefinesLen = BlobLen - 1;
+ }
break;
}
@@ -1287,7 +1297,12 @@
// Load the translation unit declaration
if (Context)
ReadDeclRecord(DeclOffsets[0], 0);
-
+
+ // Check the predefines buffer.
+ if (CheckPredefinesBuffer(PCHPredefines, PCHPredefinesLen,
+ PCHPredefinesBufferID))
+ return IgnorePCH;
+
// Initialization of builtins and library builtins occurs before the
// PCH file is read, so there may be some identifiers that were
// loaded into the IdentifierTable before we intercepted the
diff --git a/lib/Frontend/PCHWriter.cpp b/lib/Frontend/PCHWriter.cpp
index e61cca5..11f6202 100644
--- a/lib/Frontend/PCHWriter.cpp
+++ b/lib/Frontend/PCHWriter.cpp
@@ -1378,11 +1378,21 @@
// Create and write out the blob that contains the identifier
// strings.
- IdentifierOffsets.resize(IdentifierIDs.size());
{
OnDiskChainedHashTableGenerator<PCHIdentifierTableTrait> Generator;
+ // Look for any identifiers that were named while processing the
+ // headers, but are otherwise not needed. We add these to the hash
+ // table to enable checking of the predefines buffer in the case
+ // where the user adds new macro definitions when building the PCH
+ // file.
+ for (IdentifierTable::iterator ID = PP.getIdentifierTable().begin(),
+ IDEnd = PP.getIdentifierTable().end();
+ ID != IDEnd; ++ID)
+ getIdentifierRef(ID->second);
+
// Create the on-disk hash table representation.
+ IdentifierOffsets.resize(IdentifierIDs.size());
for (llvm::DenseMap<const IdentifierInfo *, pch::IdentID>::iterator
ID = IdentifierIDs.begin(), IDEnd = IdentifierIDs.end();
ID != IDEnd; ++ID) {
diff --git a/test/PCH/fuzzy-pch.c b/test/PCH/fuzzy-pch.c
index ce4634d..2ddcb8b 100644
--- a/test/PCH/fuzzy-pch.c
+++ b/test/PCH/fuzzy-pch.c
@@ -1,6 +1,8 @@
// Test with pch.
// RUN: clang-cc -emit-pch -DFOO -o %t %S/variables.h &&
-// RUN: clang-cc -DBAR=int -include-pch %t -fsyntax-only -pedantic %s
+// RUN: clang-cc -DBAR=int -include-pch %t -fsyntax-only -pedantic %s &&
+// RUN: clang-cc -DFOO -DBAR=int -include-pch %t -Werror %s &&
+// RUN: not clang-cc -DFOO -DBAR=int -DX=5 -include-pch %t -Werror %s
BAR bar = 17;