Issue with allocatable strings and O1, O2 and O3 (IFX)

[Olsen__Oystein]

Hi,

I have an issue with the IFX- compiler. The attached program works with -O0, but not -O1, -O2 and -O3. (It works with ifort, gfortran and nagfor).

Commands to compile with -O1, and to run the test program:

make O1
./bug_string

Use corresponding commands for -O0, -O2 and -O3. The expected output is:

 # --epoch#
 
 # --epoch#

With -O1 I get:

 # --     #
 
 # --     #

The weird thing is that I get the expected results if I uncomment line 65 in the code. That line only writes a few character to stdout, and should have no effect at all.

[Olsen__Oystein]

As with my other issue, this too works when adding --noauto as an option to the compiler, and works with ifort 2021.8.0.

Regards,

Øystein

[Devorah_H_Intel]

I was able to reproduce the issue reported here. This case is now escalated to compiler engineering.