Gcc Error Undefined Reference To Sqrt
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Undefined Reference To Sqrt Ubuntu
Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs undefined reference to sqrt' eclipse Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just undefined reference to sqrt makefile like you, helping each other. Join them; it only takes a minute: Sign up C - undefined reference to “sqrt” even with '-lm' up vote 8 down vote favorite I try to compile a library in C
How To Include Math.h In Gcc
that need "math.h", here is the begining of the .c file: #include
Bash ./a.out No Such File Or Directory
collect2: error: ld returned 1 exit status I don't get it after an hour of googling the issue. I'm working with gcc 4.9 under ubuntu 14.10 (utopic unicorn). Thank for any help in advance! c gcc ld math.h share|improve this question asked Dec 15 '14 at 0:57 Alexandre Pieroux 5216 The -c option suppresses linking. You won't get that error from that command line. Therefore, that isn't the command line that produces the error. (Don't use @ before rules in a makefile — it probably isn't your problem, but it hides commands and can mislead you.) And most of this is what @paxdiablo said. –Jonathan Leffler Dec 15 '14 at 1:06 possible duplicate of "undefined reference to `pow'" even with math.h and the library link -lm –Ciro Santilli 烏坎事件2016六四事件 法轮功 May 15 '15 at 20:36 add a comment| 1 Answer 1 active oldest votes up vote 9 down vote accepted I don't think that is the command you're running (well, it may be one of them, but it's certainly not the one causing your error). The -c option to gcc tells it to only create the object files (and you're specifically sending the output to sparse_matrix.o, an object file rather than an executable one). In that case, the linker should not be called at all. In fact, with
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Undefined Reference To `sqrtf'
Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 sqrt function c million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up C - undefined reference to sqrt (or other mathematical functions) up vote 30 down vote favorite 8 I have http://stackoverflow.com/questions/27475977/c-undefined-reference-to-sqrt-even-with-lm this simple code: max = (int) sqrt (number); and in the header I have: #include
Programming Boards C Programming undefined reference to `sqrt' when using math.h Getting started with C or C++ | C Tutorial | C++ Tutorial | C and C++ FAQ | Get a http://cboard.cprogramming.com/c-programming/101188-undefined-reference-%60sqrt-when-using-math-h.html compiler | Fixes for common problems Thread: undefined reference to `sqrt' when using math.h Thread Tools Show Printable Version Email this Page… Subscribe to this Thread… Display Linear Mode Switch to Hybrid Mode Switch to Threaded Mode 03-31-2008 #1 Milhas View Profile View Forum Posts Banned Join Date Mar 2008 Posts 78 undefined reference to `sqrt' when using math.h Just like the title says.. I get undefined reference to `sqrt' error and undefined reference i included math.h Using GCC by the way, in linux. 03-31-2008 #2 Cactus_Hugger View Profile View Forum Posts int x = *((int *) NULL); Join Date Jul 2003 Location Banks of the River Styx Posts 902 "undefined reference" is a linker error - meaning that you didn't link with the code for the function it's complaining about. (Most of the times, #including something will not fix this) For sqrt(), add -lm to undefined reference to your linker flags. long time; /* know C? */ Unprecedented performance: Nothing ever ran this slow before. Any sufficiently advanced bug is indistinguishable from a feature. Real Programmers confuse Halloween and Christmas, because dec 25 == oct 31. The best way to accelerate an IBM is at 9.8 m/s/s. recursion (re - cur' - zhun) n. 1. (see recursion) 03-31-2008 #3 Milhas View Profile View Forum Posts Banned Join Date Mar 2008 Posts 78 Originally Posted by Cactus_Hugger "undefined reference" is a linker error - meaning that you didn't link with the code for the function it's complaining about. (Most of the times, #including something will not fix this) For sqrt(), add -lm to your linker flags. What is a linker flags? I'm using gcc how should i do it? 03-31-2008 #4 Cactus_Hugger View Profile View Forum Posts int x = *((int *) NULL); Join Date Jul 2003 Location Banks of the River Styx Posts 902 Example: Code: $ gcc -c -o main.o main.c $ gcc -c -o second.o second.c $ gcc -o myprogram main.o second.o -lm or, if you're doing it all in one line: $ gcc -o myprogram main.c second.c -lm long time; /* know C? */ Unprecedented performance: Nothing ever ran this slow before. Any sufficiently advanced bug is indistinguishable