https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102192
Bug ID: 102192
Summary: Curious '-O2'-only '-Wmaybe-uninitialized' diagnostics
for 'libgomp.oacc-fortran/routine-10.f90'
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Keywords: diagnostic
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: tschwinge at gcc dot gnu.org
CC: burnus at gcc dot gnu.org
Blocks: 24639
Target Milestone: ---
The 'libgomp.oacc-fortran/routine-10.f90' test case as originally added in
commit 12df77ab6df4b91d4770240bcc4ab443e4bb18b9 shows curious
'-Wmaybe-uninitialized' diagnostics. Now, of course this is
'-Wmaybe-uninitialized', so may easily be dismissed "don't care", but maybe
there's something to be improved here?
For standard host compilation (no '-fopenacc'), but only with '-O2', we get
diagnosed:
libgomp.oacc-fortran/routine-10.f90:28:21: Warning: ‘c’ may be used
uninitialized in this function [-Wmaybe-uninitialized]
libgomp.oacc-fortran/routine-10.f90:21:50: note: ‘c’ was declared here
libgomp.oacc-fortran/routine-10.f90:46:30: Warning: ‘c’ may be used
uninitialized in this function [-Wmaybe-uninitialized]
libgomp.oacc-fortran/routine-10.f90:21:50: note: ‘c’ was declared here
Not seeing this with any other '-O[...]' level, and also goes away with '-O2
-fno-inline', for example. Have not quickly been able to reproduce with '-O3'
plus various '-fno-[...].
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=24639
[Bug 24639] [meta-bug] bug to track all Wuninitialized issues
