https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119856
--- Comment #14 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- Created attachment 61556 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=61556&action=edit Patch to correct runtime behavior of repeated use of the same format This patch corrects a latent problem. many years ago to improve performance, once a format string was parsed and checked for errors, the tokenized format was saved in a cache. Later, this cache is checked and if the string is found, the saved tokenized format is reused without reparsing and rechecking. So in this testcase, no error was given for the problem at line 10. program badfmt implicit none character(10):: fmt = "(AI5)" ! Not parameter, so not examined at compile time integer :: ioerr ioerr = 0 write (*, fmt, iostat=ioerr) 'value =', 42 print *, 'ioerr =', ioerr write (*, fmt) 'value =', 43 ! <--- no error found end program badfmt This patch checks to see if an error was seen before saving the parsed format. If so, it is not saved. This ensures that each use of thay particular format string is reparsed and rechecked.
