Search Results

Search found 5842 results on 234 pages for 'compiler warnings'.

Page 174/234 | < Previous Page | 170 171 172 173 174 175 176 177 178 179 180 181  | Next Page >

• C++: namespace conflicht between extern "C" and class member

  - by plaisthos

  Hi, I stumbled upon a rather exotic c++ namespace problem: condensed example: extern "C" { void solve(lprec * lp); } class A { public: lprec * lp; void solve(int foo); } void A::solve(int foo) { solve(lp); } I want to call the c funcition solve in my C++ member function A::solve. The compiler is not happy with my intents: error C2664: 'lp_solve_ilp::solve' : cannot convert parameter 1 from 'lprec *' to 'int' Is there something I can prefix the solve function? C::solve does not work

  Read the article

• Is It Safe to Cast Away volatile?

  - by Yan Cheng CHEOK

  Most of the time, I am doing this way. class a { public: ~ a() { i = 100; // OK delete (int *)j; // Compiler happy. But, is it safe? // Error : delete j; } private: volatile int i; volatile int *j; }; int main() { a aa; } However, I saw an article here: https://www.securecoding.cert.org/confluence/display/seccode/EXP32-C.+Do+not+access+a+volatile+object+through+a+non-volatile+reference Casting away volatile allows access to an object through a non-volatile reference. This can result in undefined and perhaps unintended program behavior. So, what will be the workaround for my above code example?

  Read the article

• Using module include in OCaml

  - by Geoff

  In OCaml 3.11, I want to "extend" an existing module using the include directive, like so: module MyString = struct include String let trim s = ... end No problem. But now I want to expose this module's type explicitly (i.e. in a .mli file). I want something like this: module MyString : sig include String val trim : string -> string end But the include syntax is not correct because String refers to a module, not a module type (and the compiler does indeed barf). How can I refer to the module type for String here (without having write it out explicitly in a sig expression)? Thanks!

  Read the article

• What's the best way to build software that doesn't require the newest glibc?

  - by ZorbaTHut

  I'm attempting to build a binary package that can be run on multiple Linux distributions. It's currently built on Ubuntu 10.04, but it fails on Ubuntu 8.04 with the following error: ./test: /usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.11' not found (required by ./test) ./test: /usr/lib/libstdc.so.6: version `GLIBC_2.11' not found (required by ./test) What's the preferred way to solve this problem? Is there a way to install an old glibc on a new box and build against it, or do I have to build on an old distribution? And if I build against an old glibc, will it work on a new glibc? Or, alternatively, are there just some handy compiler flags or packages I could install to solve the problem?

  Read the article

• C++/g++: Concurrent programm

  - by phimuemue

  Hi, I got a C++ program (source) that is said to work in parallel. However, if I compile it (I am using Ubuntu 10.04 and g++ 4.4.3) with g++ and run it, one of my two CPU cores gets full load while the other is doing "nothing". So I spoke to the one who gave me the program. I was told that I had to set specific flags for g++ in order to get the program compiled for 2 CPU cores. However, if I look at the code I'm not able to find any lines that point to parallelism. So I have two questions: Are there any C++-intrinsics for multithreaded applications, i.e. is it possible to write parallel code without any extra libraries (because I did not find any non-standard libraries included)? Is it true that there are indeed flags for g++ that tell the compiler to compile the program for 2 CPU cores and to compile it so it runs in parallel (and if: what are they)?

  Read the article

• My Delphi 7 application halts on Application.Initialize and does not return to next line

  - by m-abdi

  I have created an application on Delphi 7. my app had running fine since yesterday. I don't know what's happened yesterday which cause my application halts on Application.Initialize line in source code and does not return to next line when i trace the program. I can't run the created executable file from widows niether while the generated file does run on another machine correctly. here is the code where the compiler stops on it: program Info_Kiosk; uses SysUtils, Forms, ... (some other units) ; {$R *.res} begin Application.Initialize; Application.CreateForm(Tfrm_Main, frm_Main); any help would be appreciated

  Read the article

• Output Unicode to Console Using C++

  - by Jesse Foley

  I'm still learning C++, so bear with me and my sloppy code. The compiler I use is Dev C++. I want to be able to output Unicode characters to the Console using cout. Whenver i try things like: # #include directive here (include iostream) using namespace std; int main() { cout << "Hello World!\n"; cout << "Blah blah blah some gibberish unicode: ÐAßGg\n"; system("PAUSE"); return 0; } It outputs strange characters to the console, like µA¦Gg. Why does it do that, and how can i get to to display ÐAßGg? Or is this not possible with Windows?

  Read the article

• How can I force the text go to the button of the panel?

  - by Roman

  At the moment I have the following code which works fine. label = new JLabel(panelLabel,SwingConstants.CENTER); outputPanel.add(label,BorderLayout.CENTER); I get the text in the center of the panel (in terms of the left-right position as well as in terms of the top-bottom). Now I want to set the position to the bottom (and center in terms of "left-right"). I tried to use SOUTH instead of the CENTER in the first line. Compiler does not complains but during the execution i get IllegalArgumentException: HorizontalAlignment. What is that?

  Read the article

• Is there a Perl module for parsing numbers, including ranges?

  - by sid_com

  Is there a module, which does this for me? sample_input: 2, 5-7, 9, 3, 11-14 #!/usr/bin/env perl use warnings; use strict; use 5.012; sub aw_parse { my( $in, $max ) = @_; chomp $in; my @array = split ( /\s*,\s*/, $in ); my %zahlen; for ( @array ) { if ( /^\s*(\d+)\s*$/ ) { $zahlen{$1}++; } elsif ( /^\s*(\d+)\s*-\s*(\d+)\s*$/ ) { die "'$1-$2' not a valid input $!" if $1 >= $2; for ( $1 .. $2 ) { $zahlen{$_}++; } } else { die "'$_' not a valid input $!"; } } @array = sort { $a <=> $b } keys ( %zahlen ); if ( defined $max ) { for ( @array ) { die "Input '0' not allowed $!" if $_ == 0; die "Input ($_) greater than $max not allowed $!" if $_ > $max; } } return \@array; } my $max = 20; print "Input (max $max): "; my $in = <>; my $out = aw_parse( $in, $max ); say "@$out";

  Read the article

• help('modules') crashing? Not sure how to fix..

  - by Chris

  I was trying to install a module for opencv and added an opencv.pth file to the folder beyond my sites.py file. I have since deleted it and no change. When I try to run help('modules'), I get the following error: Please wait a moment while I gather a list of all available modules... /System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/twisted/words/im/init.py:8: UserWarning: twisted.im will be undergoing a rewrite at some point in the future. warnings.warn("twisted.im will be undergoing a rewrite at some point in the future.") /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pkgutil.py:110: DeprecationWarning: The wxPython compatibility package is no longer automatically generated or actively maintained. Please switch to the wx package as soon as possible. import(name) Traceback (most recent call last): File "", line 1, in File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site.py", line 348, in call return pydoc.help(*args, **kwds) File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pydoc.py", line 1644, in call self.help(request) File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pydoc.py", line 1681, in help elif request == 'modules': self.listmodules() File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pydoc.py", line 1802, in listmodules ModuleScanner().run(callback) File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pydoc.py", line 1853, in run for importer, modname, ispkg in pkgutil.walk_packages(): File "/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/pkgutil.py", line 110, in walk_packages import(name) File "/BinaryCache/wxWidgets/wxWidgets-11~262/Root/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/wxaddons/init.py", line 180, in import_hook File "/Library/Python/2.5/site-packages/ctypes_opencv/init.py", line 19, in from ctypes_opencv.cv import * File "/BinaryCache/wxWidgets/wxWidgets-11~262/Root/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/wxaddons/init.py", line 180, in import_hook File "/Library/Python/2.5/site-packages/ctypes_opencv/cv.py", line 2567, in ('desc', CvMat_r, 1), # CvMat* desc File "/Library/Python/2.5/site-packages/ctypes_opencv/cxcore.py", line 114, in cfunc return CFUNCTYPE(result, *atypes)((name, dll), tuple(aflags)) AttributeError: dlsym(0x2674d10, cvCreateFeatureTree): symbol not found What gives?!

  Read the article

• Getting list of all existing vtables.

  - by Patrick

  In my application I have quite some void-pointers (this is because of historical reasons, application was originally written in pure C). In one of my modules I know that the void-pointers points to instances of classes that could inherit from a known base class, but I cannot be 100% sure of it. Therefore, doing a dynamic_cast on the void-pointer might give problems. Possibly, the void-pointer even points to a plain-struct (so no vptr in the struct). I would like to investigate the first 4 bytes of the memory the void-pointer is pointing to, to see if this is the address of the valid vtable. I know this is platform, maybe even compiler-version-specific, but it could help me in moving the application forward, and getting rid of all the void-pointers over a limited time period (let's say 3 years). Is there a way to get a list of all vtables in the application, or a way to check whether a pointer points to a valid vtable, and whether that instance pointing to the vtable inherits from a known base class?

  Read the article

• Strange difference between optimized/non optimized microsoft c++ code

  - by Anders Forsgren

  I have a c++ program with a method that looks something like this: int myMethod(int* arr1, int* arr2, int* index) { arr1--; arr2--; int val = arr1[*index]; int val2 = arr2[val]; doMoreThings(val); } With optimizations enabled (/O2) the first line where the first pointer is decremented is not executed. I assume the compiler believes that the arr1 array is not used since it thinks it can remove the decrement. Am I violating some convention in the above code? What could cause this behavior? It is a very old piece of f2c-translated code, the pointer decrement is due to the 1-based indexing of the original code.

  Read the article

• How do I prevent race condition WITHOUT using locks in C++?

  - by Hristo

  How do I prevent a race condition WITHOUT locking or using mutexes/semaphors in C++? I'm dealing with a nested for loop in which I will be setting a value in an array: for (int i = 0; i < m; ++i) for (int j = 0; j < n; ++j) for (int k = 0; k < o; ++k) array[k] += foo(...); More or less, I want to deal with this so that I can ensure different threads running at the same time don't write to array[k] at the same time. Any suggestions on how to approach this? Edit: I am running on a Linux machine and I also have to use the Intel compiler. I will be using "icc" instead of "gcc" to compile the code.

  Read the article

• How Iostream file is located in computer by c++ code during execution

  - by user3702024

  i want to know that in a c++ code during execution how iostream file is founded. we write #include in c++ program and i know about #include which is a preprocessor directive to load files and is a file name but i don't know that how that file is located. i have some questions in my mind... Is Standard library present in compiler which we are using? Is that file is present in standard library or in our computer? Can we give directory path to locate the file through c++ code if yes then how?

  Read the article

• What features of Scala cannot be translated to Java?

  - by Paul

  The Scala compiler compiles direct to Java byte code (or .NET CIL). Some of the features of Scala could be re-done in Java straightforwardly (e.g. simple for comprehensions, classes, translating anonymous/inner functionc etc). What are the features that cannot be translated that way? That is presumably mostly of academic interest. More usefully, perhaps, what are the key features or idioms of Scala that YOU use that cannot be easily represented in Java? Are there any the other way about? Things that can be done straightforwardly in Java that have no straightforward equivalent in Scala? Idioms in Java that don't translate?

  Read the article

• Using a class with const data members in a vector

  - by Max

  Given a class like this: class Foo { const int a; }; Is it possible to put that class in a vector? When I try, my compiler tells me it can't use the default assignment operator. I try to write my own, but googling around tells me that it's impossible to write an assignment operator for a class with const data members. One post I found said that "if you made [the data member] const that means you don't want assignment to happen in the first place." This makes sense. I've written a class with const data members, and I never intended on using assignment on it, but apparently I need assignment to put it in a vector. Is there a way around this that still preserves const-correctness?

  Read the article

• Any techniques to interrupt, kill, or otherwise unwind (releasing synchronization locks) a single de

  - by gojomo

  I have a long-running process where, due to a bug, a trivial/expendable thread is deadlocked with a thread which I would like to continue, so that it can perform some final reporting that would be hard to reproduce in another way. Of course, fixing the bug for future runs is the proper ultimate resolution. Of course, any such forced interrupt/kill/stop of any thread is inherently unsafe and likely to cause other unpredictable inconsistencies. (I'm familiar with all the standard warnings and the reasons for them.) But still, since the only alternative is to kill the JVM process and go through a more lengthy procedure which would result in a less-complete final report, messy/deprecated/dangerous/risky/one-time techniques are exactly what I'd like to try. The JVM is Sun's 1.6.0_16 64-bit on Ubuntu, and the expendable thread is waiting-to-lock an object monitor. Can an OS signal directed to an exact thread create an InterruptedException in the expendable thread? Could attaching with gdb, and directly tampering with JVM data or calling JVM procedures allow a forced-release of the object monitor held by the expendable thread? Would a Thread.interrupt() from another thread generate a InterruptedException from the waiting-to-lock frame? (With some effort, I can inject an arbitrary beanshell script into the running system.) Can the deprecated Thread.stop() be sent via JMX or any other remote-injection method? Any ideas appreciated, the more 'dangerous', the better! And, if your suggestion has worked in personal experience in a similar situation, the best!

  Read the article

• Is it legal for a C++ reference to be NULL?

  - by BCS

  A while back I ran into a bug the looked something like this: void fn(int &i) { printf(&i == NULL ? "NULL\n" : "!NULL\n"); } int main() { int i; int *ip = NULL; fn(i); // prints !NULL fn(*ip); // prints NULL return 0; } More recently, I ran into this comment about C++ references: [References arguments make] it clear, unlike with pointers, that NULL is not a possible value. But, as show above, NULL is a possible value. So where is the error? In the language spec? (Unlikely.) Is the compiler in error for allowing that? Is that coding guide in error (or a little ambiguous)? Or am I just wandering into the minefield known as undefined behavior?

  Read the article

• contentscript, dynamic created iframe, postmessage

  - by thefoyer

  I'm attempting to inject an iframe from a content script. From the content script, post a message to the iframe, without much success. This is the closest I have got. No errors/warnings in the console but it doesn't work (alert test). contentscript: var iframe = document.createElement("iframe"); iframe.setAttribute("src", "https://www.com/iframe.php"); iframe.id = "iframe01"; document.getElementsByTagName("body")[0].appendChild(iframe); //then I inject this "web_accessible_resources" script var script = document.createElement("script"); script.type = "text/javascript"; script.src = chrome.extension.getURL("postMessage.js"); document.getElementsByTagName("head")[0].appendChild(script); postMessage.js window.postMessage({msg: "test"}, "*"); I've also tried top.postMessage({msg: "test"}, "*"); And var iframe = document.getElementById('iframe01'); iframe.contentWindow.postMessage({msg: "test"}, "*"); EDIT: I tried to make sure the iframe was loaded before postMessage, even if I put an alert there, it would alert telling me the iframe was loaded. var iframe = document.getElementById('iframe01'); if (ifrm_prsto.contentWindow.document) //do postMessage EDIT2: I did get it to work by moving the iframe from the contentscript to the inject.js script. Wasn't totally ideal but I do have it working now, I guess. iframe.php window.addEventListener("message", function(e) {alert("test");}); I am however able to do the reverse, talk to the parent script from the iframe.

  Read the article

• Will Windows Update modify anything in Visual Studio?

  - by Martin

  (Note: Yes, the technical side of this question seems to be rather SuperUser, but the implications are more relevant for StackOverflow readers.) As the title says, we are wondering if (fully) enabling automated Windows Updates on our developer machines will have implications for MS Visual Studio. That is, will any fixes to any components (be it libraries, UI/IDE, compiler, ...) ever be updated through Windows Update? We want to have 100% exact and reproducible development environments (wrt C++) on all developer machines, and so we are concerned that automated Windows updates may introduce some uncontrolled updates into our development chain.

  Read the article

• Does C++ require a destructor call for each placement new?

  - by Josh Haberman

  I understand that placement new calls are usually matched with explicit calls to the destructor. My question is: if I have no need for a destructor (no code to put there, and no member variables that have destructors) can I safely skip the explicit destructor call? Here is my use case: I want to write C++ bindings for a C API. In the C API many objects are accessible only by pointer. Instead of creating a wrapper object that contains a single pointer (which is wasteful and semantically confusing). I want to use placement new to construct an object at the address of the C object. The C++ object will do nothing in its constructor or destructor, and its methods will do nothing but delegate to the C methods. The C++ object will contain no virtual methods. I have two parts to this question. Is there any reason why this idea will not work in practice on any production compiler? Does this technically violate the C++ language spec?

  Read the article

• Precision problems of real numbers in Fortran

  - by saladoil

  I've been trying to use Fortran for my research project, with the GNU Fortran compiler (gfortran), latest version, but I've been encountering some problems in the way it processes real numbers. If you have for example the code: program test implicit none real :: y = 23.234, z z = y * 100000 write(*,*) y, z end program You'll get as output: 23.23999 2323400.0. I find this really strange. Can someone tell me what's exactly happening here? Looking at z I can see that y does retain its precision, so for calculations that shouldn't be a problem I suppose. But why is the output of y not exactly the same as the value that I've specified, and what can I do to make it exactly the same?

  Read the article

• Question about inserting assembly code in C++

  - by Bruce

  I am working on VC++ compiler. I want to accomplish the following The variables s.AddrFrame.Offset and s.AddrStack.Offset contain the value of EBP and ESP respectively. I want to extract the value of old EBP and the return address. Assuming the address EBP + 1 contains the old 32 bit EBP value and EBP + 5 the return address I wrote the following code: unsigned int old_ebp = 0; unsigned int ret_addr = 0; __asm{ mov old_ebp, DWORD PTR [s.AddrFrame.Offset + 1] mov ret_addr, DWORD PTR [s.AddrStack.Offset + 5] } But this is not compiling xxxx.cpp(1130) : error C2415: improper operand type Please Help

  Read the article

• C++ Translation Phase Confusion

  - by blakecl

  Can someone explain why the following doesn't work? int main() // Tried on several recent C++ '03 compilers. { #define FOO L const wchar_t* const foo = FOO"bar"; // Will error out with something like: "identifier 'L' is undefined." #undef FOO } I thought that preprocessing was done in an earlier translation phase than string literal operations and general token translation. Wouldn't the compiler be more or less seeing this: int main() { const wchar_t* const foo = L"bar"; } It would be great if someone could cite an explanation from the standard.

  Read the article

• Windows based development for ARM processors

  - by user367231

  I am a complete newbie to the ARM world. I need to be able to write C code, compile it, and then download into an ARM emulator, and execute. I need to use the GCC 4.1.2 compiler for the C code compilation. Can anybody point me in the correct directions for the following issues? What tool chain to use? What emulator to use? Are there tutorials or guides on setting up the tool chain?

  Read the article

< Previous Page | 170 171 172 173 174 175 176 177 178 179 180 181  | Next Page >