clang/tools/diagtool/ListWarnings.cpp

   1 //===- ListWarnings.h - diagtool tool for printing warning flags ----------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file provides a diagtool tool that displays warning flags for
  10 // diagnostics.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "DiagTool.h"
  15 #include "DiagnosticNames.h"
  16 #include "clang/Basic/AllDiagnostics.h"
  17 #include "clang/Basic/Diagnostic.h"
  18 #include "llvm/ADT/StringMap.h"
  19 #include "llvm/Support/Format.h"
  20
  21 DEF_DIAGTOOL("list-warnings",
  22              "List warnings and their corresponding flags",
  23              ListWarnings)
  24
  25 using namespace clang;
  26 using namespace diagtool;
  27
  28 namespace {
  29 struct Entry {
  30   llvm::StringRef DiagName;
  31   llvm::StringRef Flag;
  32
  33   Entry(llvm::StringRef diagN, llvm::StringRef flag)
  34     : DiagName(diagN), Flag(flag) {}
  35
  36   bool operator<(const Entry &x) const { return DiagName < x.DiagName; }
  37 };
  38 }
  39
  40 static void printEntries(std::vector<Entry> &entries, llvm::raw_ostream &out) {
  41   for (const Entry &E : entries) {
  42     out << "  " << E.DiagName;
  43     if (!E.Flag.empty())
  44       out << " [-W" << E.Flag << "]";
  45     out << '\n';
  46   }
  47 }
  48
  49 int ListWarnings::run(unsigned int argc, char **argv, llvm::raw_ostream &out) {
  50   std::vector<Entry> Flagged, Unflagged;
  51   llvm::StringMap<std::vector<unsigned> > flagHistogram;
  52
  53   for (const DiagnosticRecord &DR : getBuiltinDiagnosticsByName()) {
  54     const unsigned diagID = DR.DiagID;
  55
  56     if (DiagnosticIDs::isBuiltinNote(diagID))
  57       continue;
  58
  59     if (!DiagnosticIDs::isBuiltinWarningOrExtension(diagID))
  60       continue;
  61
  62     Entry entry(DR.getName(), DiagnosticIDs::getWarningOptionForDiag(diagID));
  63
  64     if (entry.Flag.empty())
  65       Unflagged.push_back(entry);
  66     else {
  67       Flagged.push_back(entry);
  68       flagHistogram[entry.Flag].push_back(diagID);
  69     }
  70   }
  71
  72   out << "Warnings with flags (" << Flagged.size() << "):\n";
  73   printEntries(Flagged, out);
  74
  75   out << "Warnings without flags (" << Unflagged.size() << "):\n";
  76   printEntries(Unflagged, out);
  77
  78   out << "\nSTATISTICS:\n\n";
  79
  80   double percentFlagged =
  81       ((double)Flagged.size()) / (Flagged.size() + Unflagged.size()) * 100.0;
  82
  83   out << "  Percentage of warnings with flags: "
  84       << llvm::format("%.4g", percentFlagged) << "%\n";
  85
  86   out << "  Number of unique flags: "
  87       << flagHistogram.size() << '\n';
  88
  89   double avgDiagsPerFlag = (double) Flagged.size() / flagHistogram.size();
  90   out << "  Average number of diagnostics per flag: "
  91       << llvm::format("%.4g", avgDiagsPerFlag) << '\n';
  92
  93   out << "  Number in -Wpedantic (not covered by other -W flags): "
  94       << flagHistogram["pedantic"].size() << '\n';
  95
  96   out << '\n';
  97
  98   return 0;
  99 }
 100