Hi Eric,
> GMP version: gmp-6.2.1-2.fc36.x86_64, installed using dnf on Fedora 36.
> Test program: a.c and b.cpp, see attachment.
> To run a.c, use "gcc a.c -o a -lgmp && ./a". The output on my machine
> is "0.1e-3215911262793760767".
> To run b.cpp, use "g++ b.cpp -o b -lgmp -lgmpxx && ./b". The output on
> my machine is "1e+-1294967296".
> The results are wrong because I entered a very large number, but got a
> number between 0 and 1. I am expecting GMP to return an error in
> mpf_init_set_str() indicating that the exponent is too large.
on gmplib.org you can read:
High-level floating-point arithmetic functions (mpf). This is the GMP function
category to use if the C type `double' doesn't give enough precision for an
application. There are about 70 functions in this category. New projects should
strongly consider using the much more complete GMP extension library mpfr
instead of mpf.
Indeed with the following MPFR program you will get:
$ gcc -g /tmp/b.c -lmpfr
$ ./a.out
@Inf@
$ cat /tmp/b.c
#include <assert.h>
#include <stdio.h>
#include <mpfr.h>
int main(void) {
mpfr_t f;
const char *s = "1e3000000000000000000000000000000";
mpfr_init_set_str(f, s, 10, MPFR_RNDN);
mpfr_out_str (stdout, 10, 100, f, MPFR_RNDN);
printf("\n");
}
Hope this helps,
Paul
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