GCC; Hint compiler that variable is initialized;
1
There is a part of code:
void func0(xxx* obj)
{
void* ptr;
size_t size;
obj->getBuffer(ptr, size); // Init ptr & size
while(size) // ERROR: may be used uninitialized
{
// processing buffer
}
}
'xxx.h'
#include <cstddef>
class xxx
{
public:
xxx();
xxx(void* p, size_t s);
void getBuf(void*& p, size_t& s);
private:
void* pp;
size_t ss;
};
'xxx.cpp'
#include "xxx.h"
xxx::xxx()
{
pp = (void*)0xFFFF;
ss = 0x100;
}
xxx::xxx(void* p, size_t s)
{
pp = p;
ss = s;
}
void xxx::getBuf(void*& p, size_t& s)
{
p = pp;
s = ss;
}
GCC generates 'may be used uninitialized in this function' error.
GCC version: 'aarch64-elf-g++ (GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23)) 8.2.1 20180802'
Is there a way to hint compiler that variables are actually inited without explicitly assign them with some default values in declaration?
PS: Error comes with a new version of toolchain.
please no 'rewrite everything' / 'bad design' advices.
c++ gcc
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
|
show 1 more comment
1
There is a part of code:
void func0(xxx* obj)
{
void* ptr;
size_t size;
obj->getBuffer(ptr, size); // Init ptr & size
while(size) // ERROR: may be used uninitialized
{
// processing buffer
}
}
'xxx.h'
#include <cstddef>
class xxx
{
public:
xxx();
xxx(void* p, size_t s);
void getBuf(void*& p, size_t& s);
private:
void* pp;
size_t ss;
};
'xxx.cpp'
#include "xxx.h"
xxx::xxx()
{
pp = (void*)0xFFFF;
ss = 0x100;
}
xxx::xxx(void* p, size_t s)
{
pp = p;
ss = s;
}
void xxx::getBuf(void*& p, size_t& s)
{
p = pp;
s = ss;
}
GCC generates 'may be used uninitialized in this function' error.
GCC version: 'aarch64-elf-g++ (GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23)) 8.2.1 20180802'
Is there a way to hint compiler that variables are actually inited without explicitly assign them with some default values in declaration?
PS: Error comes with a new version of toolchain.
please no 'rewrite everything' / 'bad design' advices.
c++ gcc
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
not exactly, my question. I'm interesting in changinggetBufferattributes. For example, for nowgetBufferassigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way thatgetBufferis used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.
– user3124812
Nov 21 '18 at 4:39
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12
|
show 1 more comment
1
1
1
1
There is a part of code:
void func0(xxx* obj)
{
void* ptr;
size_t size;
obj->getBuffer(ptr, size); // Init ptr & size
while(size) // ERROR: may be used uninitialized
{
// processing buffer
}
}
'xxx.h'
#include <cstddef>
class xxx
{
public:
xxx();
xxx(void* p, size_t s);
void getBuf(void*& p, size_t& s);
private:
void* pp;
size_t ss;
};
'xxx.cpp'
#include "xxx.h"
xxx::xxx()
{
pp = (void*)0xFFFF;
ss = 0x100;
}
xxx::xxx(void* p, size_t s)
{
pp = p;
ss = s;
}
void xxx::getBuf(void*& p, size_t& s)
{
p = pp;
s = ss;
}
GCC generates 'may be used uninitialized in this function' error.
GCC version: 'aarch64-elf-g++ (GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23)) 8.2.1 20180802'
Is there a way to hint compiler that variables are actually inited without explicitly assign them with some default values in declaration?
PS: Error comes with a new version of toolchain.
please no 'rewrite everything' / 'bad design' advices.
c++ gcc
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
There is a part of code:
void func0(xxx* obj)
{
void* ptr;
size_t size;
obj->getBuffer(ptr, size); // Init ptr & size
while(size) // ERROR: may be used uninitialized
{
// processing buffer
}
}
'xxx.h'
#include <cstddef>
class xxx
{
public:
xxx();
xxx(void* p, size_t s);
void getBuf(void*& p, size_t& s);
private:
void* pp;
size_t ss;
};
'xxx.cpp'
#include "xxx.h"
xxx::xxx()
{
pp = (void*)0xFFFF;
ss = 0x100;
}
xxx::xxx(void* p, size_t s)
{
pp = p;
ss = s;
}
void xxx::getBuf(void*& p, size_t& s)
{
p = pp;
s = ss;
}
GCC generates 'may be used uninitialized in this function' error.
GCC version: 'aarch64-elf-g++ (GNU Toolchain for the A-profile Architecture 8.2-2018-08 (arm-rel-8.23)) 8.2.1 20180802'
Is there a way to hint compiler that variables are actually inited without explicitly assign them with some default values in declaration?
PS: Error comes with a new version of toolchain.
please no 'rewrite everything' / 'bad design' advices.
c++ gcc
c++ gcc
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
edited Nov 22 '18 at 0:44
user3124812
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
asked Nov 21 '18 at 4:14
user3124812user3124812
4241517
4241517
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
not exactly, my question. I'm interesting in changinggetBufferattributes. For example, for nowgetBufferassigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way thatgetBufferis used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.
– user3124812
Nov 21 '18 at 4:39
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12
|
show 1 more comment
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
not exactly, my question. I'm interesting in changinggetBufferattributes. For example, for nowgetBufferassigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way thatgetBufferis used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.
– user3124812
Nov 21 '18 at 4:39
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
not exactly, my question. I'm interesting in changing
getBuffer attributes. For example, for now getBuffer assigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way that getBuffer is used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.– user3124812
Nov 21 '18 at 4:39
not exactly, my question. I'm interesting in changing
getBuffer attributes. For example, for now getBuffer assigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way that getBuffer is used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.– user3124812
Nov 21 '18 at 4:39
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12
|
show 1 more comment
0
active
oldest
votes
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
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53405165%2fgcc-hint-compiler-that-variable-is-initialized%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
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
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53405165%2fgcc-hint-compiler-that-variable-is-initialized%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
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
Required, but never shown
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
Required, but never shown
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
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Possible duplicate of Disable GCC "may be used uninitialized" on a particular variable
– Swordfish
Nov 21 '18 at 4:16
not exactly, my question. I'm interesting in changing
getBufferattributes. For example, for nowgetBufferassigns variables always. Lets say it's modified and skips initialization of a parameter. "-Wuninitialized" would suppress a warning, while variable is indeed uninited. Additional inconvenience of this way thatgetBufferis used in different files, all these files should be modified. Changing multiple files, rather than only one, is exactly what I want to avoid.– user3124812
Nov 21 '18 at 4:39
Cannot reproduce. Please provide a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 4:50
@PasserBy Those pieces of code should be in different compilation units. Is there an online tool which allow to create a few files? 'godbolt' and similar work with only one 'main' file and compiler effectively inline everything...
– user3124812
Nov 21 '18 at 5:55
wandbox.org. Your question is required to make sense without an external link, please edit the question to be a Minimal, Complete, and Verifiable example.
– Passer By
Nov 21 '18 at 6:12