https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69697
Eric Gallager <egallager at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |egallager at gcc dot gnu.org
--- Comment #2 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Martin Sebor from comment #1)
> Confirming. To make things worse, the program output changes between -O0
> and -O1:
>
> $ (for o in 0 1 2 3; do gcc -O$o -Wall -Wextra y.C && ./a.out; done)
> i = 0, j = 3, a = { 2, { 3, 4, } }
> i = 3, j = 0, a = { 2, { 3, 4, } }
> i = 3, j = 0, a = { 2, { 3, 4, } }
> i = 3, j = 0, a = { 2, { 3, 4, } }
I tested some additional optimization levels; -O0 is still the only different
one:
$ (for o in 0 1 2 3 g s fast; do /usr/local/bin/gcc -O${o} -Wall -Wextra
-std=c++14 -xc++ -o 69697_O${o}.exe 69697.c && printf "./69697_O${o}.exe: " &&
./69697_O${o}.exe; done)
./69697_O0.exe: i = 0, j = 3, a = { 2, { 3, 4, } }
./69697_O1.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
./69697_O2.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
./69697_O3.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
./69697_Og.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
./69697_Os.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
./69697_Ofast.exe: i = 3, j = 0, a = { 2, { 3, 4, } }
