llvm-project/clang/lib/Frontend/Warnings.cpp

131 lines
4.6 KiB
C++

//===--- Warnings.cpp - C-Language Front-end ------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Command line warning options handler.
//
//===----------------------------------------------------------------------===//
//
// This file is responsible for handling all warning options. This includes
// a number of -Wfoo options and their variants, which are driven by TableGen-
// generated data, and the special cases -pedantic, -pedantic-errors, -w,
// -Werror and -Wfatal-errors.
//
// Each warning option controls any number of actual warnings.
// Given a warning option 'foo', the following are valid:
// -Wfoo, -Wno-foo, -Werror=foo, -Wfatal-errors=foo
//
#include "clang/Frontend/Utils.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Sema/SemaDiagnostic.h"
#include "clang/Lex/LexDiagnostic.h"
#include "clang/Frontend/DiagnosticOptions.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include <cstring>
#include <utility>
#include <algorithm>
using namespace clang;
void clang::ProcessWarningOptions(Diagnostic &Diags,
const DiagnosticOptions &Opts) {
Diags.setSuppressSystemWarnings(true); // Default to -Wno-system-headers
Diags.setIgnoreAllWarnings(Opts.IgnoreWarnings);
Diags.setShowOverloads(
static_cast<Diagnostic::OverloadsShown>(Opts.ShowOverloads));
// Handle -ferror-limit
if (Opts.ErrorLimit)
Diags.setErrorLimit(Opts.ErrorLimit);
if (Opts.TemplateBacktraceLimit)
Diags.setTemplateBacktraceLimit(Opts.TemplateBacktraceLimit);
// If -pedantic or -pedantic-errors was specified, then we want to map all
// extension diagnostics onto WARNING or ERROR unless the user has futz'd
// around with them explicitly.
if (Opts.PedanticErrors)
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Error);
else if (Opts.Pedantic)
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Warn);
else
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Ignore);
for (unsigned i = 0, e = Opts.Warnings.size(); i != e; ++i) {
StringRef Opt = Opts.Warnings[i];
// Check to see if this warning starts with "no-", if so, this is a negative
// form of the option.
bool isPositive = true;
if (Opt.startswith("no-")) {
isPositive = false;
Opt = Opt.substr(3);
}
// Figure out how this option affects the warning. If -Wfoo, map the
// diagnostic to a warning, if -Wno-foo, map it to ignore.
diag::Mapping Mapping = isPositive ? diag::MAP_WARNING : diag::MAP_IGNORE;
// -Wsystem-headers is a special case, not driven by the option table. It
// cannot be controlled with -Werror.
if (Opt == "system-headers") {
Diags.setSuppressSystemWarnings(!isPositive);
continue;
}
// -Werror/-Wno-error is a special case, not controlled by the option table.
// It also has the "specifier" form of -Werror=foo and -Werror-foo.
if (Opt.startswith("error")) {
StringRef Specifier;
if (Opt.size() > 5) { // Specifier must be present.
if ((Opt[5] != '=' && Opt[5] != '-') || Opt.size() == 6) {
Diags.Report(diag::warn_unknown_warning_specifier)
<< "-Werror" << ("-W" + Opt.str());
continue;
}
Specifier = Opt.substr(6);
}
if (Specifier.empty()) {
Diags.setWarningsAsErrors(isPositive);
continue;
}
// -Werror=foo maps foo to Error, -Wno-error=foo maps it to Warning.
Mapping = isPositive ? diag::MAP_ERROR : diag::MAP_WARNING_NO_WERROR;
Opt = Specifier;
}
// -Wfatal-errors is yet another special case.
if (Opt.startswith("fatal-errors")) {
StringRef Specifier;
if (Opt.size() != 12) {
if ((Opt[12] != '=' && Opt[12] != '-') || Opt.size() == 13) {
Diags.Report(diag::warn_unknown_warning_specifier)
<< "-Wfatal-errors" << ("-W" + Opt.str());
continue;
}
Specifier = Opt.substr(13);
}
if (Specifier.empty()) {
Diags.setErrorsAsFatal(isPositive);
continue;
}
// -Wfatal-errors=foo maps foo to Fatal, -Wno-fatal-errors=foo
// maps it to Error.
Mapping = isPositive ? diag::MAP_FATAL : diag::MAP_ERROR_NO_WFATAL;
Opt = Specifier;
}
if (Diags.setDiagnosticGroupMapping(Opt, Mapping))
Diags.Report(isPositive ? diag::warn_unknown_warning_option :
diag::warn_unknown_negative_warning_option)
<< ("-W" + Opt.str());
}
}