Compiler bug - stream formatted nonadvancing read

[Jan_F_]

Hello,

I'd like to report a possible bug in Fortran Intel Compiler - it seems it doesn't read correctly data in nonadvancing way on a file opened as a formatted stream.

Please consider the attached program. It generates file with lines "This_is_line_no_XXXX" where XXXX is the number of the line. It then reads it back as stream formatted nonadvancing. With the default blocksize, the first problem exhibits at line 780 which is around 16384 bytes which could be the default blocksize, the output is as follows:

[jan@olney npen_build]$ ./test.exe
 Generating file fread_test.txt
 Reading fread_test.txt
OK  Line    1 read   20 >This_is_line_no_0001<
OK  Line    2 read   20 >This_is_line_no_0002<
OK  Line    3 read   20 >This_is_line_no_0003<
...
OK  Line  776 read   20 >This_is_line_no_0776<
OK  Line  777 read   20 >This_is_line_no_0777<
OK  Line  778 read   20 >This_is_line_no_0778<
OK  Line  779 read   20 >This_is_line_no_0779<
ERR Line  780 read   40 >This_is_line_no_0780This_is_line_no_0781<
ERR Line  781 read   20 >This_is_line_no_0782<
ERR Line  782 read   20 >This_is_line_no_0783<

If blocksize=200 as in the attached program, the problem exhibits much more often in all kind of strange ways:

...
OK  Line  145 read   20 >This_is_line_no_0145<
ERR Line  146 read   22 >Thihis_is_line_no_0147<
ERR Line  147 read   20 >This_is_line_no_0148<
...
ERR Line  193 read   20 >This_is_line_no_0194<
ERR Line  194 read   18 >This_is_line_no_01<
ERR Line  195 read   20 >This_is_line_no_0196<
...
ERR Line  241 read   20 >This_is_line_no_0242<
ERR Line  242 read   24 >This_iss_is_line_no_0244<
ERR Line  243 read   20 >This_is_line_no_0245<
...
ERR Line  289 read   20 >This_is_line_no_0291<
ERR Line  290 read   14 >This_is_line92<
ERR Line  291 read   20 >This_is_line_no_0293<
...

The output is generated from ifort (IFORT) 15.0.2 20150121 64-bit on Fedora 21, however, the similar behavior can be reproduced on Windows with Intel(R) Visual Fortran Intel(R) 64 Compiler XE for applications running on Intel(R) 64, Version 15.0.4.221 Build 20150407

Regards,

Jan

[Ron_Green]

thanks for bringing this to our attention.  Let me run a few tests and get a bug report entered.

Ron

[Ron_Green]

The bug report is entered.

We will keep you posted on progress.

Ron

[Steven_L_Intel1]

This bug is fixed in compiler version 17.0, available now.