Re: Bug#1119833: src:stress-ng: fails to migrate to testing for too long: FTBFS on s390x

[Pranav P <pranav.p7@ibm.com>]

Hi Paul,

Seems like on line 154 in the Makefile:

> ifneq ($(MACHINE),$(filter $(MACHINE),ibms390 s390))
> override CFLAGS += $(foreach flag,-fmodulo-sched,$(cc_supports_flag))
> endif

the variable $(MACHINE) is receiving the value 'make[1]: Entering directory ...
s390 make[1]: Leaving directory ...' instead of just 's390'. This causes the if condition
to execute causing the `-fmodulo-sched` flag to be enabled triggering the issue.

running make with --no-print-directory seems to fix the issue. So, maybe a simple
change in the rules file should do.

But at the same time, although it doesn't make much sense to enable `-fmodulo-sched`
in an out-of-order architecture like s390x, it shouldn't cause the compiler to loop
indefinitely. So, I will try to extract a test case where I can reproduce the issue and will
try to communicate with the compiler team here at IBM.

Either ways, that if condition is not supposed to run. I tried doing an sbuild after adding
--no-print-directory in the rules file and with that it seems to build fine (autopkgtest also passes).

Thanks,
Pranav