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

109 lines
4.0 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 and
// -Werror.
//
// Each warning option controls any number of actual warnings.
// Given a warning option 'foo', the following are valid:
// -Wfoo, -Wno-foo, -Werror=foo
//
#include "clang/Frontend/Utils.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Sema/SemaDiagnostic.h"
#include "clang/Lex/LexDiagnostic.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include <cstdio>
#include <cstring>
#include <utility>
#include <algorithm>
using namespace clang;
bool clang::ProcessWarningOptions(Diagnostic &Diags,
std::vector<std::string> &Warnings,
bool Pedantic, bool PedanticErrors,
bool NoWarnings) {
Diags.setSuppressSystemWarnings(true); // Default to -Wno-system-headers
Diags.setIgnoreAllWarnings(NoWarnings);
// 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 (PedanticErrors)
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Error);
else if (Pedantic)
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Warn);
else
Diags.setExtensionHandlingBehavior(Diagnostic::Ext_Ignore);
// FIXME: -Wfatal-errors / -Wfatal-errors=foo
for (unsigned i = 0, e = Warnings.size(); i != e; ++i) {
const std::string &Opt = Warnings[i];
const char *OptStart = &Opt[0];
const char *OptEnd = OptStart+Opt.size();
assert(*OptEnd == 0 && "Expect null termination for lower-bound search");
// Check to see if this warning starts with "no-", if so, this is a negative
// form of the option.
bool isPositive = true;
if (OptEnd-OptStart > 3 && memcmp(OptStart, "no-", 3) == 0) {
isPositive = false;
OptStart += 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 (OptEnd-OptStart == 14 && memcmp(OptStart, "system-headers", 14) == 0) {
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 (OptEnd-OptStart >= 5 && memcmp(OptStart, "error", 5) == 0) {
const char *Specifier = 0;
if (OptEnd-OptStart != 5) { // Specifier must be present.
if ((OptStart[5] != '=' && OptStart[5] != '-') ||
OptEnd-OptStart == 6) {
fprintf(stderr, "warning: unknown -Werror warning specifier: -W%s\n",
Opt.c_str());
continue;
}
Specifier = OptStart+6;
}
if (Specifier == 0) {
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;
OptStart = Specifier;
}
if (Diags.setDiagnosticGroupMapping(OptStart, Mapping))
Diags.Report(FullSourceLoc(), diag::warn_unknown_warning_option)
<< ("-W" + Opt);
}
return false;
}