[modules] Stop trying to fake up a linear MacroDirective history.
Modules builds fundamentally have a non-linear macro history. In the interest
of better source fidelity, represent the macro definition information
faithfully: we have a linear macro directive history within each module, and at
any point we have a unique "latest" local macro directive and a collection of
visible imported directives. This also removes the attendent complexity of
attempting to create a correct MacroDirective history (which we got wrong
in the general case).
No functionality change intended.
llvm-svn: 236176
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index fdaf7e2..f6602c8 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1084,79 +1084,51 @@
// not have changed.
if (!Id->hadMacroDefinition())
return;
+ auto *LatestLocalMD = PP.getLocalMacroDirectiveHistory(Id);
- // If this identifier does not currently have a macro definition,
- // check whether it had one on the command line.
- if (!Id->hasMacroDefinition()) {
- MacroDirective::DefInfo LatestDef =
- PP.getMacroDirectiveHistory(Id)->getDefinition();
- for (MacroDirective::DefInfo Def = LatestDef; Def;
- Def = Def.getPreviousDefinition()) {
- FileID FID = SourceMgr.getFileID(Def.getLocation());
- if (FID.isInvalid())
- continue;
-
- // We only care about the predefines buffer.
- if (FID != PP.getPredefinesFileID())
- continue;
-
- // This macro was defined on the command line, then #undef'd later.
- // Complain.
- PP.Diag(ImportLoc, diag::warn_module_config_macro_undef)
- << true << ConfigMacro << Mod->getFullModuleName();
- if (LatestDef.isUndefined())
- PP.Diag(LatestDef.getUndefLocation(), diag::note_module_def_undef_here)
- << true;
- return;
- }
-
- // Okay: no definition in the predefines buffer.
- return;
- }
-
- // This identifier has a macro definition. Check whether we had a definition
- // on the command line.
- MacroDirective::DefInfo LatestDef =
- PP.getMacroDirectiveHistory(Id)->getDefinition();
- MacroDirective::DefInfo PredefinedDef;
- for (MacroDirective::DefInfo Def = LatestDef; Def;
- Def = Def.getPreviousDefinition()) {
- FileID FID = SourceMgr.getFileID(Def.getLocation());
- if (FID.isInvalid())
- continue;
-
+ // Find the macro definition from the command line.
+ MacroInfo *CmdLineDefinition = nullptr;
+ for (auto *MD = LatestLocalMD; MD; MD = MD->getPrevious()) {
// We only care about the predefines buffer.
- if (FID != PP.getPredefinesFileID())
+ FileID FID = SourceMgr.getFileID(MD->getLocation());
+ if (FID.isInvalid() || FID != PP.getPredefinesFileID())
continue;
-
- PredefinedDef = Def;
+ if (auto *DMD = dyn_cast<DefMacroDirective>(MD))
+ CmdLineDefinition = DMD->getMacroInfo();
break;
}
- // If there was no definition for this macro in the predefines buffer,
- // complain.
- if (!PredefinedDef ||
- (!PredefinedDef.getLocation().isValid() &&
- PredefinedDef.getUndefLocation().isValid())) {
+ auto *CurrentDefinition = PP.getMacroInfo(Id);
+ if (CurrentDefinition == CmdLineDefinition) {
+ // Macro matches. Nothing to do.
+ } else if (!CurrentDefinition) {
+ // This macro was defined on the command line, then #undef'd later.
+ // Complain.
+ PP.Diag(ImportLoc, diag::warn_module_config_macro_undef)
+ << true << ConfigMacro << Mod->getFullModuleName();
+ auto LatestDef = LatestLocalMD->getDefinition();
+ assert(LatestDef.isUndefined() &&
+ "predefined macro went away with no #undef?");
+ PP.Diag(LatestDef.getUndefLocation(), diag::note_module_def_undef_here)
+ << true;
+ return;
+ } else if (!CmdLineDefinition) {
+ // There was no definition for this macro in the predefines buffer,
+ // but there was a local definition. Complain.
PP.Diag(ImportLoc, diag::warn_module_config_macro_undef)
<< false << ConfigMacro << Mod->getFullModuleName();
- PP.Diag(LatestDef.getLocation(), diag::note_module_def_undef_here)
+ PP.Diag(CurrentDefinition->getDefinitionLoc(),
+ diag::note_module_def_undef_here)
<< false;
- return;
+ } else if (!CurrentDefinition->isIdenticalTo(*CmdLineDefinition, PP,
+ /*Syntactically=*/true)) {
+ // The macro definitions differ.
+ PP.Diag(ImportLoc, diag::warn_module_config_macro_undef)
+ << false << ConfigMacro << Mod->getFullModuleName();
+ PP.Diag(CurrentDefinition->getDefinitionLoc(),
+ diag::note_module_def_undef_here)
+ << false;
}
-
- // If the current macro definition is the same as the predefined macro
- // definition, it's okay.
- if (LatestDef.getMacroInfo() == PredefinedDef.getMacroInfo() ||
- LatestDef.getMacroInfo()->isIdenticalTo(*PredefinedDef.getMacroInfo(),PP,
- /*Syntactically=*/true))
- return;
-
- // The macro definitions differ.
- PP.Diag(ImportLoc, diag::warn_module_config_macro_undef)
- << false << ConfigMacro << Mod->getFullModuleName();
- PP.Diag(LatestDef.getLocation(), diag::note_module_def_undef_here)
- << false;
}
/// \brief Write a new timestamp file with the given path.