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

Prevent cppcoreguidelines-pro-bounds-array-to-pointer-decay from diagnosing array to pointer decay stemming from system macros. 

Patch by Breno Rodrigues Guimaraes.

llvm-svn: 298421
This commit is contained in:
Aaron Ballman 2017-03-21 19:01:17 +00:00
parent 9c1e310c16
commit 163e7166d7
2 changed files with 29 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsArrayToPointerDecayCheck.cpp
View File

@ -47,6 +47,25 @@ AST_MATCHER_P(Expr, hasParentIgnoringImpCasts,
return InnerMatcher.matches(*E, Finder, Builder);
}
AST_MATCHER(ImplicitCastExpr, isArrayToPointerDecay) {
return Node.getCastKind() == CK_ArrayToPointerDecay;
}
AST_MATCHER(ImplicitCastExpr, sysSymbolDecayInSysHeader) {
auto &SM = Finder->getASTContext().getSourceManager();
if (SM.isInSystemMacro(Node.getLocStart())) {
if (isa<PredefinedExpr>(Node.getSubExpr()))
return true;
if (const auto *SymbolDeclRef = dyn_cast<DeclRefExpr>(Node.getSubExpr())) {
const ValueDecl *SymbolDecl = SymbolDeclRef->getDecl();
if (SymbolDecl && SM.isInSystemHeader(SymbolDecl->getLocation()))
return true;
}
}
return false;
}
void ProBoundsArrayToPointerDecayCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus)
return;
@ -56,10 +75,12 @@ void ProBoundsArrayToPointerDecayCheck::registerMatchers(MatchFinder *Finder) {
// 2) inside a range-for over an array
// 3) if it converts a string literal to a pointer
Finder->addMatcher(
implicitCastExpr(unless(hasParent(arraySubscriptExpr())),
implicitCastExpr(isArrayToPointerDecay(),
unless(hasParent(arraySubscriptExpr())),
unless(hasParentIgnoringImpCasts(explicitCastExpr())),
unless(isInsideOfRangeBeginEndStmt()),
unless(hasSourceExpression(stringLiteral())))
unless(hasSourceExpression(stringLiteral())),
unless(sysSymbolDecayInSysHeader()))
.bind("cast"),
this);
}
@ -67,8 +88,6 @@ void ProBoundsArrayToPointerDecayCheck::registerMatchers(MatchFinder *Finder) {
void ProBoundsArrayToPointerDecayCheck::check(
const MatchFinder::MatchResult &Result) {
const auto *MatchedCast = Result.Nodes.getNodeAs<ImplicitCastExpr>("cast");
if (MatchedCast->getCastKind() != CK_ArrayToPointerDecay)
return;
diag(MatchedCast->getExprLoc(), "do not implicitly decay an array into a "
"pointer; consider using gsl::array_view or "

6
clang-tools-extra/test/clang-tidy/cppcoreguidelines-pro-bounds-array-to-pointer-decay.cpp
View File

@ -1,4 +1,5 @@
// RUN: %check_clang_tidy %s cppcoreguidelines-pro-bounds-array-to-pointer-decay %t
#include <assert.h>
#include <stddef.h>
namespace gsl {
@ -34,6 +35,11 @@ void f() {
for (auto &e : a) // OK, iteration internally decays array to pointer
e = 1;
assert(false); // OK, array decay inside system header macro
assert(a);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: do not implicitly decay an array into a pointer; consider using gsl::array_view or an explicit cast instead [cppcoreguidelines-pro-bounds-array-to-pointer-decay]
}
const char *g() {