Dear all,
I try to compile the following two programs on my recent cygwin/XP with
gcc 3.4.4:
PROGRAM A:
---------------------------
#include <math.h>
long double F(long double K){ return(powl(K,K)); }
main()
{
printf("%Lf \n",F(3.));
}
---------------------------
PROGRAM B:
---------------------------
#include <math.h>
long double F(long double K){ return(powl(K,1)); }
main()
{
printf("%Lf \n",F(3.));
}
---------------------------
Note that the only difference is "1" instead of "K" on line 3.
I compile by following command:
gcc blan.c -lm
In case A the answer of gcc is
/cygdrive/c/Temp/ccEHzDhs.o:blan.c:(.text+0x30): undefined reference to
`_powl'
collect2: ld gaf exit-status 1 terug
In case B the program compiles without any problem and returns correct
answer when run. Both programs compile when substituting "pow" for
"powl". The switch "-lm" makes no difference(!), the result is exactly
the same without it.
I must say this is a puzzle for me. Especially as the "nm libm.a | grep
pow" in my /lib and /usr/lib says
00000000 T __f_pow
00000000 I __imp___f_pow
00000000 T __f_powf
00000000 I __imp___f_powf
00000000 I __imp__pow
00000000 T _pow
00000000 I __imp__powf
00000000 T _powf
indicating that (strangely) there isn't any powl in my libm !?
Can anybody tell me what could be going on ?
Thanks,
David
