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Linker Error Undefined Reference To Main


For example, assuming "grades" is a vector of some kind, the warning is generated by this code for (int i = 0; i < grades.size( ); i++ { // body of Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count). Is there a mutual or positive way to say "Give me an inch and I'll take a mile"? To do that, you'll need another .cpp source file that has a #include "list.h" and a main() function. click site

Learn about the distinction between declaring a variable, class or function--and defining it--and why it matters when you have trouble compiling or linking your code Learn more about dealing with compiler But it's a real question, so no closing. –Omnifarious Jan 28 '13 at 8:13 1 Sorry it's been almost a year since I last used c++. First, you should always (since you are a newbie) compile with gcc -Wall -g -c es3.c gcc -Wall -g es3.o -o es3 The -Wall flag is extremely important, and you should The form is int main(void) { ...; return 0; } Any thoughts on why I might get this error?

Undefined Reference To Main Gcc

Is there a difference between u and c in mknod What to do with my out of control pre teen daughter Box around continued fraction Referee did not fully understand accepted On the other hand, sometimes the problem is with the directives to the linker; on more than one occasion, I've seen people include multiple copies of the same object file in Is it correct to write "teoremo X statas, ke" in the sense of "theorem X states that"? For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration.

Investigating C++11 Threads Common C++ Error Messages #1 - No such file ordirectory Learning Go – Miniblog #14 – Closures andGoroutines Learning Go – Miniblog #13 – More On ServerObjects Learning If you're faced with a list of fifty or sixty error and warning messages, it can be daunting to even try to figure out where to start. Its telling you exactly what is wrong. Undefined Reference To Main Makefile Alien_Hominid View Public Profile View LQ Blog View Review Entries View HCL Entries Find More Posts by Alien_Hominid 05-25-2011, 04:25 PM #13 yaa see LQ Newbie Registered: May 2011

Handling Cryptic or Bizarre Messages There are several types of compiler errors that are especially frustrating. Below is my result. $ objdump -t es3.o es3.o: file format elf32-i386 SYMBOL TABLE: 00000000 l df *ABS* 00000000 es3.c 00000000 l d .text 00000000 .text 00000000 l d .data 00000000 Any ideas as to why this error occurs? Either post the code as part of your question, or narrow it down to a small example that illustrates the problem and post that. –Keith Thompson Nov 2 '11 at 3:58

Not the answer you're looking for? Undefined Reference To Main Error In C In many cases, the previous post may not be available to people reading your post. non-aggregate type -- classes and structs are generically called "aggregate" types. Any ideas?

Undefined Reference To Main In Function _start

If you get an error indicating that your class is a "non-aggregate type", then the compiler has not seen your class definition and doesn't recognize your class as such. http://www.cprogramming.com/tutorial/compiler_linker_errors.html It keeps popping up the following error: /usr/lib/gcc/i386-redhat-linux/4.0.0/../../../crt1.o(.text+0x18): In function `_start': >undefined reference to `main' collect2: ld returned 1 exit status This happens whether I compile the code using a makefile Undefined Reference To Main Gcc Join them; it only takes a minute: Sign up Undefined reference to main - collect2: ld returned 1 exit status up vote 18 down vote favorite 1 I'm trying to compile Undefined Reference To Main C++ The main function is simply doing nothing at this point, but checking for command line arguments.

The first is the case of an undeclared variable that you swear you declared. get redirected here ostream copy constructor is private Example /usr/local/lib/gcc-lib/i686-pc-linux-gnu/3.2.1/include/c++/bits/ios_base.h: In copy constructor `std::basic_ios >::basic_ios(const std::basic_ios&)': /usr/local/lib/gcc-lib/i686-pc-linux-gnu/3.2.1/include/c++/bits/ios_base.h:424: `std::ios_base::ios_base(const std::ios_base&)' is private mil.cpp:28: within this context mil.cpp: In function `int main()': mil.cpp:28: A single error near the top of your program can cause a cascade of other compiler errors because those lines might rely on something early in the program that the compiler This can be hard when you're just starting out, but if you pay attention to the messages and try to pick out what they could mean, you'll quickly get used to Undefined Reference To Main G++

identifier -- the name of a class, struct, function or variable collect2: ld returned 1 exit status -- usually found as the last line of the error. Although the compiler would have expected a semicolon, it would also have expected a conditional expression, so the error message you get might be something like "line 53, unexpected parenthesis ')'". This can happen if you forget to include the main function at all, or if you attempt to compile code that was never meant to be a stand-alone executable (for instance, navigate to this website Although you don't want to ignore them, compiler warnings aren't something severe enough to actually keep your program from compiling.

For instance, even if you include the correct header files for all of your functions, you still need to provide your linker with the correct path to the library that has Undefined Reference To Main Assembly If you'd like to contribute content, let us know. For instance, closing curly braces or closing quotes.

For example, if you write your class definition in myClass.cc, and your main function is in myMain.cc, your compiler will create two object files, myClass.o and myMain.o, and the linker will

Dissecting an Error Message Most messages from the compiler will consist of at least four things: the type of message--warning or error--source code file in which the error appeared, and the How do you grow in a skill when you're the company lead in that area? These are compiled separately, using the C++ compiler, to produce object code files (files with a .o or a .obj extension) which contain machine code. In Function Start Undefined Reference To Main Oct 6 '06 #1 Post Reply Share this Question 8 Replies P: n/a Thomas Tutone owolablo wrote: I'm making a project involving some C++ source files.

Wrong Project Type The linker error regarding WinMain above can occur in a number of situations, particularly when you are using a C++ IDE such as CodeBlocks or Visual Studio. Typically the 2 step process is hidden in these cases. Your problem is that you do not have the object file which contains your main function, so the linker is giving you an undefined reference error. http://softacoustik.com/undefined-reference/linker-error-undefined-reference-to-c.php So we get the error (slightly edited for clarity): a.cpp:(.text+0xc): undefined reference to `foo()' error: ld returned 1 exit status The way to fix it is to provide the definition: int

discards qualifier Example myfile.cpp: In function `int main()': myfile.cpp:20: passing `const DayOfYear' as `this' argument of `void DayOfYear::Set(int, int)' discards qualifiers Meaning You have an inconsistency with the use of "const" Dave Kelly View Public Profile View LQ Blog View Review Entries View HCL Entries Visit Dave Kelly's homepage! undefined reference to `main' P: n/a owolablo I'm making a project involving some C++ source files. share|improve this answer edited Nov 2 '11 at 7:58 answered Nov 1 '11 at 13:58 Basile Starynkevitch 123k895203 yes i'm using Ubuntu!

It does the same for any libraries (.a and .lib files) you may be using. You need to add it: $ gcc -o runexp runexp.c scd.o data_proc.o -lm -fopenmp share|improve this answer answered Apr 9 '13 at 14:52 unwind 255k38332460 add a comment| up vote 1 If you have included such a definition, post it, and we can take a look. I started trying to figure out what the make file is actually doing.

Red balls and Rings Why does Mal change his mind? Your problem would seem to be that you have multiple executables in the same project, and that one or more of them does not have a main. Dave Kelly View Public Profile View LQ Blog View Review Entries View HCL Entries Visit Dave Kelly's homepage! Thanks.

To avoid this problem, take some care when writing declarations and definitions, and remember that things like references, pointers and const all count towards making a function signature unique. Click Here to receive this Complete Guide absolutely free. Unfortunately, this means that if you leave off a semicolon, the compiler will interpret it as though the next thing in the program is intended to be a struct (or return asked 3 years ago viewed 46774 times active 1 year ago Related 1Error linking with gcc1Cuda mixed C project linking1undefined reference to `main' in C-2Undefined reference to ''main" in a C

Oct 9, 2014 - 09:18 PM (Reply to #2) 12345Total votes: 0 I'm not too sure what you mean. Show us your real code. (The downloaded source file is 73 lines, which is short enough to post here directly.) –Keith Thompson Nov 2 '11 at 4:03 The error But it’s not magic – like all errors it means that you have done something wrong, in you code and/or your project’s configuration, and you need to take some time to This phrase indicates that you have a linker (ld) error, not a compiler error.

Nevertheless, compiler warnings aren't going to stop you from getting your program working (unless you tell your compiler to treat warnings as errors), so they're probably a bit less frustrating than