Top Forums Programming Undefined reference to omp_get_thread_num using OpenMP? Post 302942163 by larry burns on Friday 24th of April 2015 10:36:28 PM
Undefined reference to omp_get_thread_num using OpenMP?

I am using a large code-base that compiled successfully before using
Code:
make

with a makefile and cmake. However, now that I'm trying to use openmp with it, I'm now getting the errors

Code:
undefined reference to `omp_get_thread_num'
    undefined reference to `omp_get_num_threads'

I don't think this is a problem with tthe CMakeLists.txt file, because I created a seperate directory and successfully built and compiled a helloworld OpenMP program. So what is causing this error?

I edited the CMakeLists.txt in
Code:
project/src/project

so to include
Code:
-fopenmp

so it contains the line

Code:
set(CMAKE_CXX_FLAGS "-Wall -pedantic -Wextra -fopenmp")
     ....
      TARGET_LINK_LIBRARIES(PROJECT  ${OpenMP_CXX_LIBRARIES} ${PROJECT_LINK_LIBS}).

The CMakeLists.txt already has the lines

Code:
FIND_PACKAGE( OpenMP)
      if(OPENMP_FOUND)
         message("OPENMP FOUND")
         set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
         set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${OpenMP_EXE_LINKER_FLAGS}")
      endif()
     include_directories(SYSTEM ${OpenMP_INCLUDE_PATH})

Although if I type
Code:
cmake ..

, I see the output
Code:
OPENMP FOUND

, I don't see
Code:
fopenmp

in any of the makefiles and I didn't see
Code:
CXXFLAGS

OR
Code:
LDFLAGS

in any of the makefiles.

Last edited by Don Cragun; 04-25-2015 at 01:01 AM.. Reason: Fix CODE tag.
 
Test Your Knowledge in Computers #14
Difficulty: Easy
The F9 function key needs to be pressed during a Windows reboot to enter into Safe Mode.
True or False?

9 More Discussions You Might Find Interesting

1. Programming

Undefined reference to Error

Hello, plz help me out with this error, i am getting this error when i compile my code with gcc. /usr/lib/gcc-lib/i386-redhat-linux/3.3.2/../../../crt1.o(.text+0x18): In function `_start': : undefined reference to `main' /tmp/cciLxqdV.o(.text+0x3c): In function `HandleUserTransaction()':... (2 Replies)
Discussion started by: svh
2 Replies

2. Programming

about undefined reference for 'sinf'

I m writting code in c using another library(parapin) and making Makefile .but there is a error like undefined reference to `sinf' undefined reference to `ceilf' although i have added math.h library in my code . I tried to run simple programme using math.h and it run.but in making Makefile it... (2 Replies)
Discussion started by: bharat suthar
2 Replies

3. Programming

undefined reference to `pthread_create'

Hi I wanted to learn communication between threads and I used a simple example but I faced with this error while I have a sofware that uses this functions without any problem so would you please help me to know the reason thanks for your help and great favor. #include <pthread.h>... (2 Replies)
Discussion started by: netman
2 Replies

4. Programming

undefined reference to `__ctype_b'

when i compile my program, i meet the following error: ... undefined reference to `__ctype_b' ... anybody knows which shared library should be linked during make? thanks a lot! (6 Replies)
Discussion started by: princelinux
6 Replies

5. Programming

undefined reference to 'function'

Hi, i want to compile a code where fortran calls c . First I compiled C module ,it has pass by gcc. However, after generating .o file. I compiled C and fortran files together by intel fortran and it failed " undefined reference to 'vicerror'". vicerror is a function. I do not know why. (1 Reply)
Discussion started by: austinhsu
1 Replies

6. Programming

undefined reference to pthread_create

I try to compile a sample c code in fedora eclipse 3.2 as managed makefile using pthread library,it shows some error on pthread functions.Error is of undefined reference to pthread.Anybody guide me to solve this problem. Thanking you (1 Reply)
Discussion started by: sujith4u87
1 Replies

7. Programming

undefined reference to `pthread_create'

Hi guys. H was learning posix threads in C with anjuta IDE. it gives me undefined reference to `pthread_create' I know i should compile it like: gcc -lpthread main.c how should i import this configuration in anjuta so i can compile inside it? (2 Replies)
Discussion started by: majid.merkava
2 Replies

8. Homework & Coursework Questions

undefined reference help

Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted! 1. The problem statement, all variables and given/known data: i know when undefined reference shows up the program is saying it is not link to that function but the problem... (1 Reply)
Discussion started by: mgyeah
1 Replies

9. Homework & Coursework Questions

undefined reference help

Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted! 1. The problem statement, all variables and given/known data: The problem is a function which i typed although it kept saying that it is a undefined reference still. other... (1 Reply)
Discussion started by: mgyeah
1 Replies

Featured Tech Videos

All times are GMT -4. The time now is 02:43 PM.
Unix & Linux Forums Content Copyright 1993-2020. All Rights Reserved.
Privacy Policy