Introduce a limit on the depth of the macro instantiation backtrace
printed in a diagnostic, similar to the limit we already have on the
depth of the template instantiation backtrace. The macro instantiation
backtrace is limited to 10 "instantiated from:" diagnostics; when it's
longer than that, we'll show the first half, then say how many were
suppressed, then show the second half. The limit can be changed with
-fmacro-instantiation-limit=N, and turned off with N=0.
This eliminates a lot of note spew with libraries making use of the
Boost.Preprocess library.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@103014 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/TextDiagnosticPrinter.cpp b/lib/Frontend/TextDiagnosticPrinter.cpp
index 28bb17a..66ed956 100644
--- a/lib/Frontend/TextDiagnosticPrinter.cpp
+++ b/lib/Frontend/TextDiagnosticPrinter.cpp
@@ -285,7 +285,10 @@
const SourceManager &SM,
const FixItHint *Hints,
unsigned NumHints,
- unsigned Columns) {
+ unsigned Columns,
+ unsigned OnMacroInst,
+ unsigned MacroSkipStart,
+ unsigned MacroSkipEnd) {
assert(LangOpts && "Unexpected diagnostic outside source file processing");
assert(!Loc.isInvalid() && "must have a valid source location here");
@@ -293,10 +296,16 @@
// instantiated (recursively) then emit information about where the token was
// spelled from.
if (!Loc.isFileID()) {
+ // Whether to suppress printing this macro instantiation.
+ bool Suppressed
+ = OnMacroInst >= MacroSkipStart && OnMacroInst < MacroSkipEnd;
+
+
SourceLocation OneLevelUp = SM.getImmediateInstantiationRange(Loc).first;
// FIXME: Map ranges?
- EmitCaretDiagnostic(OneLevelUp, Ranges, NumRanges, SM, 0, 0, Columns);
-
+ EmitCaretDiagnostic(OneLevelUp, Ranges, NumRanges, SM, 0, 0, Columns,
+ OnMacroInst + 1, MacroSkipStart, MacroSkipEnd);
+
// Map the location.
Loc = SM.getImmediateSpellingLoc(Loc);
@@ -308,26 +317,38 @@
Ranges[i] = SourceRange(S, E);
}
- // Get the pretty name, according to #line directives etc.
- PresumedLoc PLoc = SM.getPresumedLoc(Loc);
+ if (!Suppressed) {
+ // Get the pretty name, according to #line directives etc.
+ PresumedLoc PLoc = SM.getPresumedLoc(Loc);
- // If this diagnostic is not in the main file, print out the "included from"
- // lines.
- if (LastWarningLoc != PLoc.getIncludeLoc()) {
- LastWarningLoc = PLoc.getIncludeLoc();
- PrintIncludeStack(LastWarningLoc, SM);
+ // If this diagnostic is not in the main file, print out the
+ // "included from" lines.
+ if (LastWarningLoc != PLoc.getIncludeLoc()) {
+ LastWarningLoc = PLoc.getIncludeLoc();
+ PrintIncludeStack(LastWarningLoc, SM);
+ }
+
+ if (DiagOpts->ShowLocation) {
+ // Emit the file/line/column that this expansion came from.
+ OS << PLoc.getFilename() << ':' << PLoc.getLine() << ':';
+ if (DiagOpts->ShowColumn)
+ OS << PLoc.getColumn() << ':';
+ OS << ' ';
+ }
+ OS << "note: instantiated from:\n";
+
+ EmitCaretDiagnostic(Loc, Ranges, NumRanges, SM, Hints, NumHints, Columns,
+ OnMacroInst + 1, MacroSkipStart, MacroSkipEnd);
+ return;
}
-
- if (DiagOpts->ShowLocation) {
- // Emit the file/line/column that this expansion came from.
- OS << PLoc.getFilename() << ':' << PLoc.getLine() << ':';
- if (DiagOpts->ShowColumn)
- OS << PLoc.getColumn() << ':';
- OS << ' ';
+
+ if (OnMacroInst == MacroSkipStart) {
+ // Tell the user that we've skipped contexts.
+ OS << "note: (skipping " << (MacroSkipEnd - MacroSkipStart)
+ << " contexts in backtrace; use -fmacro-backtrace-limit=0 to see "
+ "all)\n";
}
- OS << "note: instantiated from:\n";
-
- EmitCaretDiagnostic(Loc, Ranges, NumRanges, SM, Hints, NumHints, Columns);
+
return;
}
@@ -866,10 +887,29 @@
}
}
+ unsigned MacroInstSkipStart = 0, MacroInstSkipEnd = 0;
+ if (DiagOpts && DiagOpts->MacroBacktraceLimit && !LastLoc.isFileID()) {
+ // Compute the length of the macro-instantiation backtrace, so that we
+ // can establish which steps in the macro backtrace we'll skip.
+ SourceLocation Loc = LastLoc;
+ unsigned Depth = 0;
+ do {
+ ++Depth;
+ Loc = LastLoc.getManager().getImmediateInstantiationRange(Loc).first;
+ } while (!Loc.isFileID());
+
+ if (Depth > DiagOpts->MacroBacktraceLimit) {
+ MacroInstSkipStart = DiagOpts->MacroBacktraceLimit / 2 +
+ DiagOpts->MacroBacktraceLimit % 2;
+ MacroInstSkipEnd = Depth - DiagOpts->MacroBacktraceLimit / 2;
+ }
+ }
+
EmitCaretDiagnostic(LastLoc, Ranges, NumRanges, LastLoc.getManager(),
Info.getFixItHints(),
Info.getNumFixItHints(),
- DiagOpts->MessageLength);
+ DiagOpts->MessageLength,
+ 0, MacroInstSkipStart, MacroInstSkipEnd);
}
OS.flush();