maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[clang-tidy] Fix some false positives in google-readability-casting 

Summary:
Ignore C-style casts in extern "C" {} sections. Be more careful when
detecting redundant casts between typedefs to the same type - emit a more
specific warning and don't automatically fix them.

Reviewers: klimek

Reviewed By: klimek

Subscribers: curdeius, cfe-commits

Differential Revision: http://reviews.llvm.org/D7247

llvm-svn: 227444
This commit is contained in:
Alexander Kornienko 2015-01-29 15:17:13 +00:00
parent 7a24104293
commit 78070fbae5
3 changed files with 65 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
clang-tools-extra/clang-tidy/google/AvoidCStyleCastsCheck.cpp
View File

@ -68,19 +68,30 @@ void AvoidCStyleCastsCheck::check(const MatchFinder::MatchResult &Result) {
if (CastExpr->getTypeAsWritten()->isVoidType())
return;
QualType SourceType =
CastExpr->getSubExprAsWritten()->getType().getCanonicalType();
QualType DestType = CastExpr->getTypeAsWritten().getCanonicalType();
QualType SourceType = CastExpr->getSubExprAsWritten()->getType();
QualType DestType = CastExpr->getTypeAsWritten();
if (SourceType == DestType) {
diag(CastExpr->getLocStart(), "Redundant cast to the same type.")
diag(CastExpr->getLocStart(), "redundant cast to the same type")
<< FixItHint::CreateRemoval(ParenRange);
return;
}
SourceType = SourceType.getCanonicalType();
DestType = DestType.getCanonicalType();
if (SourceType == DestType) {
diag(CastExpr->getLocStart(),
"possibly redundant cast between typedefs of the same type");
return;
}
// The rest of this check is only relevant to C++.
if (!Result.Context->getLangOpts().CPlusPlus)
return;
// Ignore code inside extern "C" {} blocks.
if (!match(expr(hasAncestor(linkageSpecDecl())), *CastExpr, *Result.Context)
.empty())
return;
// Leave type spelling exactly as it was (unlike
// getTypeAsWritten().getAsString() which would spell enum types 'enum X').
@ -94,7 +105,7 @@ void AvoidCStyleCastsCheck::check(const MatchFinder::MatchResult &Result) {
diag(CastExpr->getLocStart(), "C-style casts are discouraged. %0");
auto ReplaceWithCast = [&](StringRef CastType) {
diag_builder << ("Use " + CastType + ".").str();
diag_builder << ("Use " + CastType).str();
const Expr *SubExpr = CastExpr->getSubExprAsWritten()->IgnoreImpCasts();
std::string CastText = (CastType + "<" + DestTypeString + ">").str();
@ -108,6 +119,7 @@ void AvoidCStyleCastsCheck::check(const MatchFinder::MatchResult &Result) {
}
diag_builder << FixItHint::CreateReplacement(ParenRange, CastText);
};
// Suggest appropriate C++ cast. See [expr.cast] for cast notation semantics.
switch (CastExpr->getCastKind()) {
case CK_NoOp:
@ -145,7 +157,7 @@ void AvoidCStyleCastsCheck::check(const MatchFinder::MatchResult &Result) {
break;
}
diag_builder << "Use static_cast/const_cast/reinterpret_cast.";
diag_builder << "Use static_cast/const_cast/reinterpret_cast";
}
} // namespace readability

2
clang-tools-extra/test/clang-tidy/google-readability-casting.c
View File

@ -3,7 +3,7 @@
void f(const char *cpc) {
const char *cpc2 = (const char*)cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: Redundant cast to the same type. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: redundant cast to the same type [google-readability-casting]
// CHECK-FIXES: const char *cpc2 = cpc;
char *pc = (char*)cpc;
}

67
clang-tools-extra/test/clang-tidy/google-readability-casting.cpp
View File

@ -9,67 +9,83 @@ struct Y : public X {};
void f(int a, double b, const char *cpc, const void *cpv, X *pX) {
const char *cpc2 = (const char*)cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: Redundant cast to the same type. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: redundant cast to the same type [google-readability-casting]
// CHECK-FIXES: const char *cpc2 = cpc;
typedef const char *Typedef1;
typedef const char *Typedef2;
Typedef1 t1;
(Typedef2)t1;
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: possibly redundant cast between typedefs of the same type [google-readability-casting]
// CHECK-FIXES: {{^}} (Typedef2)t1;
(const char*)t1;
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: possibly redundant cast {{.*}}
// CHECK-FIXES: {{^}} (const char*)t1;
(Typedef1)cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: possibly redundant cast {{.*}}
// CHECK-FIXES: {{^}} (Typedef1)cpc;
(Typedef1)t1;
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: redundant cast to the same type
// CHECK-FIXES: {{^}} t1;
char *pc = (char*)cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: C-style casts are discouraged. Use const_cast [google-readability-casting]
// CHECK-FIXES: char *pc = const_cast<char*>(cpc);
char *pc2 = (char*)(cpc + 33);
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char *pc2 = const_cast<char*>(cpc + 33);
const char &crc = *cpc;
char &rc = (char&)crc;
// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char &rc = const_cast<char&>(crc);
char &rc2 = (char&)*cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char &rc2 = const_cast<char&>(*cpc);
char ** const* const* ppcpcpc;
char ****ppppc = (char****)ppcpcpc;
// CHECK-MESSAGES: :[[@LINE-1]]:20: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:20: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char ****ppppc = const_cast<char****>(ppcpcpc);
char ***pppc = (char***)*(ppcpcpc);
// CHECK-MESSAGES: :[[@LINE-1]]:18: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:18: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char ***pppc = const_cast<char***>(*(ppcpcpc));
char ***pppc2 = (char***)(*ppcpcpc);
// CHECK-MESSAGES: :[[@LINE-1]]:19: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:19: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-FIXES: char ***pppc2 = const_cast<char***>(*ppcpcpc);
char *pc5 = (char*)(const char*)(cpv);
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: C-style casts are discouraged. Use const_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-2]]:22: warning: C-style casts are discouraged. Use reinterpret_cast. {{.*}}
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: {{.*}}. Use const_cast {{.*}}
// CHECK-MESSAGES: :[[@LINE-2]]:22: warning: {{.*}}. Use reinterpret_cast {{.*}}
// CHECK-FIXES: char *pc5 = const_cast<char*>(reinterpret_cast<const char*>(cpv));
int b1 = (int)b;
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: C-style casts are discouraged. Use static_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: {{.*}}. Use static_cast {{.*}}
// CHECK-FIXES: int b1 = static_cast<int>(b);
Y *pB = (Y*)pX;
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: C-style casts are discouraged. Use static_cast/const_cast/reinterpret_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: {{.*}}. Use static_cast/const_cast/reinterpret_cast {{.*}}
Y &rB = (Y&)*pX;
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: C-style casts are discouraged. Use static_cast/const_cast/reinterpret_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: {{.*}}. Use static_cast/const_cast/reinterpret_cast {{.*}}
const char *pc3 = (const char*)cpv;
// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: C-style casts are discouraged. Use reinterpret_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: {{.*}}. Use reinterpret_cast {{.*}}
// CHECK-FIXES: const char *pc3 = reinterpret_cast<const char*>(cpv);
char *pc4 = (char*)cpv;
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: C-style casts are discouraged. Use static_cast/const_cast/reinterpret_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: {{.*}}. Use static_cast/const_cast/reinterpret_cast {{.*}}
// CHECK-FIXES: char *pc4 = (char*)cpv;
b1 = (int)Enum1;
// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: C-style casts are discouraged. Use static_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: {{.*}}. Use static_cast {{.*}}
// CHECK-FIXES: b1 = static_cast<int>(Enum1);
Enum e = (Enum)b1;
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: C-style casts are discouraged. Use static_cast. [google-readability-casting]
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: {{.*}}. Use static_cast {{.*}}
// CHECK-FIXES: Enum e = static_cast<Enum>(b1);
// CHECK-MESSAGES-NOT: warning:
@ -84,10 +100,10 @@ void f(int a, double b, const char *cpc, const void *cpv, X *pX) {
template <typename T>
void template_function(T t, int n) {
int i = (int)t;
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: C-style casts are discouraged. Use static_cast/const_cast/reinterpret_cast.
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: {{.*}}. Use static_cast/const_cast/reinterpret_cast {{.*}}
// CHECK-FIXES: int i = (int)t;
int j = (int)n;
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: Redundant cast to the same type.
// CHECK-MESSAGES: :[[@LINE-1]]:11: warning: redundant cast to the same type
// CHECK-FIXES: int j = n;
}
@ -95,10 +111,10 @@ template <typename T>
struct TemplateStruct {
void f(T t, int n) {
int k = (int)t;
// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: C-style casts are discouraged. Use static_cast/const_cast/reinterpret_cast.
// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: {{.*}}. Use static_cast/const_cast/reinterpret_cast
// CHECK-FIXES: int k = (int)t;
int l = (int)n;
// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: Redundant cast to the same type.
// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: redundant cast to the same type
// CHECK-FIXES: int l = n;
}
};
@ -110,6 +126,15 @@ void test_templates() {
TemplateStruct<double>().f(1.0, 42);
}
extern "C" {
void extern_c_code(const char *cpc) {
const char *cpc2 = (const char*)cpc;
// CHECK-MESSAGES: :[[@LINE-1]]:22: warning: redundant cast to the same type
// CHECK-FIXES: const char *cpc2 = cpc;
char *pc = (char*)cpc;
}
}
#define CAST(type, value) (type)(value)
void macros(double d) {
int i = CAST(int, d);