This question already has an answer here:
CS50 get_string error linker command failed with exit code 1
(1 answer)
Closed 13 days ago.
I have the following code:
#include <cs50.h>
#include <stdio.h>
int main(void)
{
int x = get_int("whats x? ");
int y = get_int("whats y? ");
if (x < y)
{
printf("x is less than y\n");
}
}
It keeps giving me this error
moutarrjallow#Moutarrs-MBP cclang % make ccompare
cc ccompare.c -o ccompare
Undefined symbols for architecture x86_64:
"_get_int", referenced from:
_main in ccompare-91f0e5.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [ccompare] Error 1
You need to link with the cs50 library by adding the -lcs50 to above. In your Makefile you can probably do that by setting LDLIBS := -lcs50.
Related
So I'm currently new to C right now, and I just downloaded the cs50 library. I tried to make an input by using get_int(), but it's not working. Here's my code:
#include <cs50.h>
#include <stdio.h>
int main(void)
{
int i = get_int("Input: ");
printf("Output: %i\n", i);
}
This is the error that I got
cc calculator.c -o calculator
Undefined symbols for architecture x86_64:
"_get_int", referenced from:
_main in calculator-225c65.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [calculator] Error 1
This question already has answers here:
What is an undefined reference/unresolved external symbol error and how do I fix it?
(39 answers)
Closed 9 months ago.
extrn.c
#include <stdio.h>
extern int var;
int main()
{
printf("%d", var);
return 0;
}
var.c
int var = 5;
I go to file extrn.c and I run the code and I get this:
undefined reference to `var'
and this is what my output is looking like:
[Running] cd "/home/buff/Documents/Coding/C/C_programming_NESO/" && gcc extrn.c -o extrn && "/home/buff/Documents/Coding/C/C_programming_NESO/"
/usr/bin/ld: /tmp/ccoKgi02.o: in function `main':
extrn.c:(.text+0xa): undefined reference to `var'
collect2: error: ld returned 1 exit status
[Done] exited with code=1 in 0.093 seconds
Compile your both C files together to fix this undefined reference error.
For GCC
gcc extrn.c var.c -o main
For clang
clang extrn.c var.c -o main
This question already has answers here:
What is an undefined reference/unresolved external symbol error and how do I fix it?
(39 answers)
Closed 3 years ago.
I have a simple program as
demo_use.c
#include "libhello.h"
int main(void) {
hello();
return 0;
}
libhello.h
void hello(void);
libhello.c
#include <stdio.h>
void hello(void) {
printf("Hello, library world.\n");
}
I have used the command in terminal as
gcc demo_use.c -o test
error
Undefined symbols for architecture x86_64: "_hello",
referenced from: _main in ccZdSQP3.o
ld: symbol(s) not found for architecture x86_64 collect2: ld returned 1 exit status
You need to compile both the source files together to generate the binary. use
gcc demo_use.c libhello.c -o test
Otherwise, the definition of hello() function will be absent. So, at linking time, linker will throw undefined symbol error.
I realize this has probably been answered but I just cannot find it. When using "make" to compile the following file:
#include <cs50.h>
#include <stdio.h>
#include <string.h>
int main(void)
{
// get line of text
string s = GetString();
// print string, one character per line
for (int i = 0; i < strlen(s); i++)
{
char c = s[i];
printf("%c\n", c);
}
return 0;
}
I get the following message:
$ make example
cc example.c -o example
Undefined symbols for architecture x86_64:
"_GetString", referenced from:
_main in example-iPNXBe.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [example] Error 1
Judging from the cs50 page you probably need something like -lcs50 at the end of the cc command.
Or you can just use the cs50.o object file and link with it.
cc example.c cs50.o -o example
This question already has answers here:
Why do you have to link the math library in C?
(14 answers)
Closed 9 years ago.
I need to use logs in a program for an assignment. I ran this test program on my machine to see how the log function works (and if it would), and I get the following error during build.
Code
/* log example */
#include <stdio.h> /* printf */
#include <math.h> /* log */
int main()
{
double param, result;
param = 5.5;
result = log (param);
printf ("log(%f) = %f\n", param, result );
return 0;
}
ERROR
gcc -Wall -o "test" "test.c" (in directory: /home/linux/Development/codetest)
/tmp/ccCDqX7x.o: In function `main':
test.c:(.text+0x1b): undefined reference to `log'
collect2: ld returned 1 exit status
Compilation failed.
Link
This is C99 code, grabbed from this tutorial site.
Add -lm to your compilation command to link in the math library.
gcc -Wall -o "test" "test.c" -lm