Created attachment 1133484 [details]
preprocessed source file

cfitsio test case segfaults when built with -O2, but runs correctly with -O1 or -mno-lra (Jakub, thanks for the hint :-))


gcc -o testprog -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 testprog.i -L. -lcfitsio -lz -lm -lpthread


from GDB

...
Program received signal SIGSEGV, Segmentation fault.
main () at testprog.c:2209
2209	        printf(" %2.0f", doutarray[jj]);
Missing separate debuginfos, use: dnf debuginfo-install zlib-1.2.8-10.fc24.s390x
(gdb) where
#0  main () at testprog.c:2209
(gdb) l
2204	        printf(" %2.0f", eoutarray[jj]);
2205	      printf(" %d\nD", status);
2206	
2207	      ffgcvd(fptr, 8, ii, 1, ii, 99., doutarray, &anynull, &status);
2208	      for (jj = 0; jj < ii; jj++)
2209	        printf(" %2.0f", doutarray[jj]);
2210	      printf(" %d\n", status);
2211	
2212	      ffgdes(fptr, 8, ii, &repeat, &offset, &status);
2213	      printf("Column 8 repeat and offset = %ld %ld\n", repeat, offset);
(gdb) 


koji build is http://s390.koji.fedoraproject.org/koji/taskinfo?taskID=2139659
more info will follow

Version-Release number of selected component (if applicable):
gcc-6.0.0-0.14.fc24.s390x
but I got the segfault also from -15