Sfdwhf

Forgetting the musical notes while performing in concert

What's the difference between 'rename' and 'mv'?

Arrow those variables!

Can a rocket refuel on Mars from water?

Alternative to sending password over mail?

If a Gelatinous Cube takes up the entire space of a Pit Trap, what happens when a creature falls into the trap but succeeds on the saving throw?

Western buddy movie with a supernatural twist where a woman turns into an eagle at the end

Is "remove commented out code" correct English?

Can I ask the recruiters in my resume to put the reason why I am rejected?

Is it inappropriate for a student to attend their mentor's dissertation defense?

Is the Joker left-handed?

Why are electrically insulating heatsinks so rare? Is it just cost?

Watching something be written to a file live with tail

How can saying a song's name be a copyright violation?

Can a virus destroy the BIOS of a modern computer?

Why is Collection not simply treated as Collection<?>

If human space travel is limited by the G force vulnerability, is there a way to counter G forces?

Why is the 'in' operator throwing an error with a string literal instead of logging false?

Theorems that impeded progress

Why does Arabsat 6A need a Falcon Heavy to launch

Why is it a bad idea to hire a hitman to eliminate most corrupt politicians?

Can I use a neutral wire from another outlet to repair a broken neutral?

I Accidentally Deleted a Stock Terminal Theme

What is the PIE reconstruction for word-initial alpha with rough breathing?

Is delete *p an alternative to delete [] p?

In what context one may need to dynamically allocate pointers to functions?What are the differences between a pointer variable and a reference variable in C++?PHP: Delete an element from an arrayDeleting array elements in JavaScript - delete vs spliceWhy is “using namespace std” considered bad practice?What is the “-->” operator in C++?What is the copy-and-swap idiom?Why are elementwise additions much faster in separate loops than in a combined loop?Why is reading lines from stdin much slower in C++ than Python?Why is it faster to process a sorted array than an unsorted array?Why should I use a pointer rather than the object itself?

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}

11

The following code is from the Microsoft Documentation

int (**p) () = new (int (*[7]) ());

delete *p;

I think that delete [] p should be used here instead.

Is delete *p the same as delete [] p?

c++ arrays

share|improve this question

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  delete *p differs from delete [] p.
  
  – Jarod42
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're right. They're not the same.
  
  – Cruz Jean
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  typedef would make thing clearer.
  
  – Jarod42
  5 hours ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Anyway p[0] is not initialized. They have typo.
  
  – Jarod42
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  delete[] what was new[]ed and delete what was newed. Though in modern code you should avoid most uses of new, it's no longer the preferred way of dynamically creating objects. See std::make_unique and std::make_shared instead or use a standard container.
  
  – François Andrieux
  5 hours ago
  
  
  

  
  
  
  

add a comment | 

11

The following code is from the Microsoft Documentation

int (**p) () = new (int (*[7]) ());

delete *p;

I think that delete [] p should be used here instead.

Is delete *p the same as delete [] p?

c++ arrays

share|improve this question

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  delete *p differs from delete [] p.
  
  – Jarod42
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You're right. They're not the same.
  
  – Cruz Jean
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  typedef would make thing clearer.
  
  – Jarod42
  5 hours ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Anyway p[0] is not initialized. They have typo.
  
  – Jarod42
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  delete[] what was new[]ed and delete what was newed. Though in modern code you should avoid most uses of new, it's no longer the preferred way of dynamically creating objects. See std::make_unique and std::make_shared instead or use a standard container.
  
  – François Andrieux
  5 hours ago
  
  
  

  
  
  
  

add a comment | 

The following code is from the Microsoft Documentation

int (**p) () = new (int (*[7]) ());

delete *p;

I think that delete [] p should be used here instead.

Is delete *p the same as delete [] p?

c++ arrays

share|improve this question

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

int (**p) () = new (int (*[7]) ());

delete *p;

share|improve this question

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

share|improve this question

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

edited 5 hours ago

Guillaume Racicot

16.1k53871

edited 5 hours ago

Guillaume Racicot

16.1k53871

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

asked 5 hours ago

xiaokaoyxiaokaoy

7152719

2 Answers
2

active

oldest

votes

12

That code is invalid C++, because only pointers-to-objects can be deleted. *p has type int (*)(), which is a function pointer, not a pointer to an object.

Even MSVC itself does not compile it, even in permissive mode:

error C2541: 'delete': cannot delete objects that are not pointers

They should have used delete [] instead.

share|improve this answer

edited 5 hours ago

answered 5 hours ago

AcornAcorn

6,20111341

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  In what context one may need to dynamically allocate pointers to functions?
  
  – Ayxan
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan That would be another question, but for instance you may want to have a list of arbitrary operations to execute.
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan I have quickly posted it here: stackoverflow.com/q/55524710/9305398
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Even though this is specific to MSVC, g++ gives the following similar error when trying to compile: error: cannot delete expression of type 'int (*)()' .. seems odd that MS would have missed something that simple in their docs :/
  
  – txtechhelp
  3 hours ago
  
  
  

  
  
  
  

add a comment | 

-3

1. This code specifically has a different issue as it tries to delete an inner element of an array so it will not compile. It would compile if you wrote delete p and not delete *p.


2. You can use simple delete on an object allocated by new [] if It is an array of primitive types. Bad practice, ugly, yes. But not a mistake.


3. The difference between delete and delete [] is that the former also calls destructors. For primitive types, however, it will call simple delete to free the memory internally anyway.


4. Again, even if it works, you should avoid mixing operator types.

share|improve this answer

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  delete [] calls destructors...
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Mixing operators is undefined behavior.
  
  – Ayxan
  4 hours ago
  

  
  
  
  

add a comment | 

Your Answer

StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55524140%2fis-delete-p-an-alternative-to-delete-p%23new-answer', 'question_page');
}
);

Post as a guest

Name

Email

Required, but never shown

12

That code is invalid C++, because only pointers-to-objects can be deleted. *p has type int (*)(), which is a function pointer, not a pointer to an object.

Even MSVC itself does not compile it, even in permissive mode:

error C2541: 'delete': cannot delete objects that are not pointers

They should have used delete [] instead.

share|improve this answer

edited 5 hours ago

answered 5 hours ago

AcornAcorn

6,20111341

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  In what context one may need to dynamically allocate pointers to functions?
  
  – Ayxan
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan That would be another question, but for instance you may want to have a list of arbitrary operations to execute.
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan I have quickly posted it here: stackoverflow.com/q/55524710/9305398
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Even though this is specific to MSVC, g++ gives the following similar error when trying to compile: error: cannot delete expression of type 'int (*)()' .. seems odd that MS would have missed something that simple in their docs :/
  
  – txtechhelp
  3 hours ago
  
  
  

  
  
  
  

add a comment | 

12

That code is invalid C++, because only pointers-to-objects can be deleted. *p has type int (*)(), which is a function pointer, not a pointer to an object.

Even MSVC itself does not compile it, even in permissive mode:

error C2541: 'delete': cannot delete objects that are not pointers

They should have used delete [] instead.

share|improve this answer

edited 5 hours ago

answered 5 hours ago

AcornAcorn

6,20111341

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  In what context one may need to dynamically allocate pointers to functions?
  
  – Ayxan
  5 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan That would be another question, but for instance you may want to have a list of arbitrary operations to execute.
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Ayxan I have quickly posted it here: stackoverflow.com/q/55524710/9305398
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Even though this is specific to MSVC, g++ gives the following similar error when trying to compile: error: cannot delete expression of type 'int (*)()' .. seems odd that MS would have missed something that simple in their docs :/
  
  – txtechhelp
  3 hours ago
  
  
  

  
  
  
  

add a comment | 

That code is invalid C++, because only pointers-to-objects can be deleted. *p has type int (*)(), which is a function pointer, not a pointer to an object.

Even MSVC itself does not compile it, even in permissive mode:

error C2541: 'delete': cannot delete objects that are not pointers

They should have used delete [] instead.

share|improve this answer

edited 5 hours ago

answered 5 hours ago

AcornAcorn

6,20111341

error C2541: 'delete': cannot delete objects that are not pointers

share|improve this answer

edited 5 hours ago

answered 5 hours ago

AcornAcorn

6,20111341

answered 5 hours ago

AcornAcorn

6,20111341

answered 5 hours ago

AcornAcorn

6,20111341

-3

1. This code specifically has a different issue as it tries to delete an inner element of an array so it will not compile. It would compile if you wrote delete p and not delete *p.


2. You can use simple delete on an object allocated by new [] if It is an array of primitive types. Bad practice, ugly, yes. But not a mistake.


3. The difference between delete and delete [] is that the former also calls destructors. For primitive types, however, it will call simple delete to free the memory internally anyway.


4. Again, even if it works, you should avoid mixing operator types.

share|improve this answer

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  delete [] calls destructors...
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Mixing operators is undefined behavior.
  
  – Ayxan
  4 hours ago
  

  
  
  
  

add a comment | 

-3

1. This code specifically has a different issue as it tries to delete an inner element of an array so it will not compile. It would compile if you wrote delete p and not delete *p.


2. You can use simple delete on an object allocated by new [] if It is an array of primitive types. Bad practice, ugly, yes. But not a mistake.


3. The difference between delete and delete [] is that the former also calls destructors. For primitive types, however, it will call simple delete to free the memory internally anyway.


4. Again, even if it works, you should avoid mixing operator types.

share|improve this answer

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  delete [] calls destructors...
  
  – Acorn
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Mixing operators is undefined behavior.
  
  – Ayxan
  4 hours ago
  

  
  
  
  

add a comment | 

1. This code specifically has a different issue as it tries to delete an inner element of an array so it will not compile. It would compile if you wrote delete p and not delete *p.


2. You can use simple delete on an object allocated by new [] if It is an array of primitive types. Bad practice, ugly, yes. But not a mistake.


3. The difference between delete and delete [] is that the former also calls destructors. For primitive types, however, it will call simple delete to free the memory internally anyway.


4. Again, even if it works, you should avoid mixing operator types.

share|improve this answer

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

share|improve this answer

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614

answered 4 hours ago

Yuri NudelmanYuri Nudelman

1,4081614