Bug#677972: cpl: fftw not found on ia64, s390x

[Ole Streicher]

The detection failure is due to the following program run by configure
(from m4/cpl.m4):
--------------------------8<------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fftw3.h>

int main(void) {
    char vmin[] = "3.1.2";
    char *vstr    = strdup(fftw_version);
    char *vlib    = vstr;
    char *suffix  = NULL;

    int min_major = 0;
    int min_minor = 0;
    int min_micro = 0;

    int lib_major = 0;
    int lib_minor = 0;
    int lib_micro = 0;

    vlib = strchr(vstr, '-') + 1;
    suffix = strrchr(vlib, '-');

    if (suffix) {
	*suffix = '\0';
    }

    sscanf(vmin, "%d.%d.%d", &min_major, &min_minor, &min_micro);
    sscanf(vlib, "%d.%d.%d", &lib_major, &lib_minor, &lib_micro);

    FILE* f = fopen("conftest.out", "w");
    fprintf(f, "%s\n", vlib);
    fclose(f);

    free(vstr);

    if (lib_major < min_major) {
	return 1;
    } else {
	if (lib_major == min_major) {
	    if (lib_minor <  min_minor) {
		return 1;
	    } else {
		if (lib_minor == min_minor) {
		    if (lib_micro < min_micro) {
			return 1;
		    }
		}
	    }
	}
    }

    return 0;

}
--------------------------8<------------------------------------

Since the output prints with the version number "4.13.4" the wcslib
version number, I suspect that the program is actually run on these
platform -- either it silently crashes, or it does not compile at all.