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Differential D129420

[clang-tidy] Initialize boolean variables with 'false' in cppcoreguidelines-init-variables' fix-it
ClosedPublic

Authored by SimplyDanny on Jul 9 2022, 4:35 AM.

Details

Reviewers
aaron.ballman
njames93
Commits
rG33e212954430: [clang-tidy] Initialize boolean variables with `false` in cppcoreguidelines…
Summary

In case of a variable with a built-in boolean type, false is a better fit to default-initialize it.

Diff Detail

Event Timeline

SimplyDanny created this revision.Jul 9 2022, 4:35 AM
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Herald added subscribers: carlosgalvezp, shchenz, kbarton and 2 others. · View Herald Transcript
SimplyDanny requested review of this revision.Jul 9 2022, 4:35 AM
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SimplyDanny added a comment.Jul 9 2022, 4:37 AM

This is a potential fix for this issue.

Harbormaster completed remote builds in B174506: Diff 443429.Jul 9 2022, 4:58 AM
njames93 added a subscriber: njames93.Jul 9 2022, 4:59 AM

Can you add a line to release notes about this fix then LGTM

njames93 accepted this revision.Jul 9 2022, 4:59 AM
This revision is now accepted and ready to land.Jul 9 2022, 4:59 AM
Closed by commit rG33e212954430: [clang-tidy] Initialize boolean variables with `false` in cppcoreguidelines… (authored by SimplyDanny). · Explain WhyJul 9 2022, 5:50 AM
This revision was automatically updated to reflect the committed changes.
SimplyDanny added a commit: rG33e212954430: [clang-tidy] Initialize boolean variables with `false` in cppcoreguidelines….
SimplyDanny added a comment.Jul 9 2022, 5:51 AM
In D129420#3640482, @njames93 wrote:

Can you add a line to release notes about this fix then LGTM

Sure. Thank you for the fast review!

njames93 added inline comments.Jul 9 2022, 6:03 AM
clang-tools-extra/docs/ReleaseNotes.rst
188 ↗(On Diff #443434)

It should live here instead.

250–253 ↗(On Diff #443434)

Sorry I should've mentioned, we keep this list in alphabetical order(for the names of the checks).
Can you push a patch to move this into its correct place(no need for a review and commit as NFC)

SimplyDanny marked an inline comment as done.Jul 9 2022, 6:48 AM
SimplyDanny added inline comments.
clang-tools-extra/docs/ReleaseNotes.rst
250–253 ↗(On Diff #443434)

Ah sorry. I could have noticed that. Fixed in this commit.

Revision Contents

PathSize
clang-tools-extra/
clang-tidy/
cppcoreguidelines/
2 lines
test/
clang-tidy/
checkers/
cppcoreguidelines/
2 lines

Diff 443429

clang-tools-extra/clang-tidy/cppcoreguidelines/InitVariablesCheck.cpp

Show First 20 Lines • Show All 78 Lines • ▼ Show 20 Lines if (MatchedDecl->getEndLoc().isMacroID())
return; return;
QualType TypePtr = MatchedDecl->getType(); QualType TypePtr = MatchedDecl->getType();
llvm::Optional<const char *> InitializationString = llvm::None; llvm::Optional<const char *> InitializationString = llvm::None;
bool AddMathInclude = false; bool AddMathInclude = false;
if (TypePtr->isEnumeralType()) if (TypePtr->isEnumeralType())
InitializationString = nullptr; InitializationString = nullptr;
else if (TypePtr->isBooleanType())
InitializationString = " = false";
else if (TypePtr->isIntegerType()) else if (TypePtr->isIntegerType())
InitializationString = " = 0"; InitializationString = " = 0";
else if (TypePtr->isFloatingType()) { else if (TypePtr->isFloatingType()) {
InitializationString = " = NAN"; InitializationString = " = NAN";
AddMathInclude = true; AddMathInclude = true;
} else if (TypePtr->isAnyPointerType()) { } else if (TypePtr->isAnyPointerType()) {
if (getLangOpts().CPlusPlus11) if (getLangOpts().CPlusPlus11)
InitializationString = " = nullptr"; InitializationString = " = nullptr";
Show All 22 Lines

clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/init-variables.cpp

Show First 20 Lines • Show All 58 Lines • ▼ Show 20 Linesvoid init_unit_tests() {
float fval = 85.0; float fval = 85.0;
double d; double d;
// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: variable 'd' is not initialized [cppcoreguidelines-init-variables] // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: variable 'd' is not initialized [cppcoreguidelines-init-variables]
// CHECK-FIXES: {{^}} double d = NAN;{{$}} // CHECK-FIXES: {{^}} double d = NAN;{{$}}
double dval = 99.0; double dval = 99.0;
bool b; bool b;
// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: variable 'b' is not initialized [cppcoreguidelines-init-variables] // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: variable 'b' is not initialized [cppcoreguidelines-init-variables]
// CHECK-FIXES: {{^}} bool b = 0;{{$}} // CHECK-FIXES: {{^}} bool b = false;{{$}}
bool bval = true; bool bval = true;
const char *ptr; const char *ptr;
// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: variable 'ptr' is not initialized [cppcoreguidelines-init-variables] // CHECK-MESSAGES: :[[@LINE-1]]:15: warning: variable 'ptr' is not initialized [cppcoreguidelines-init-variables]
// CHECK-FIXES: {{^}} const char *ptr = nullptr;{{$}} // CHECK-FIXES: {{^}} const char *ptr = nullptr;{{$}}
const char *ptrval = "a string"; const char *ptrval = "a string";
UnusedStruct u; UnusedStruct u;
▲ Show 20 Lines • Show All 51 Lines • Show Last 20 Lines