Hello,

On Fedora so far we have been compiling micropython in a way that utilizes the default compiler flags provided by the respective Makefile's, however when a change was implemented distribution wide, to apply the default compiler flags everywhere, we stumbled upon some issues.

The compiler options added are:

-O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64  -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection

More specifically, the first issue was the addition of -Wformat-security which required a missing -Wformat option. That was easily worked around by injecting the proper flag, however -Wformat could be a welcome addition to the various Makefile's.

After the workaround and compiling the interpreter, many tests failed and then the test run hanged on x86_64. This issue did not affect the i686 architecture.

I'm attaching a full build log of a successful and a failed run.

build_log_default.txt
build_log_flags.txt