Re: overriding default compile flags when building python extensions
Ansgar wrote: On Fri, 2019-05-03 at 19:49 +0800, Drew Parsons wrote: > The first -g is the problem (in "-DNDEBUG -g -fwrapv -O2 -Wall"). Not sure about setup.py, but `-g0` (after `-g`) should also disable debug information: +--- | Level 0 produces no debug information at all. Thus, -g0 negates -g. +--- Thanks Ansgar. Weird (dangerous, even) if the flags can't be controlled directly. But I can try the -g0 trick and see if it solves the problem. Drew
Re: overriding default compile flags when building python extensions
On Fri, 2019-05-03 at 19:49 +0800, Drew Parsons wrote: > The first -g is the problem (in "-DNDEBUG -g -fwrapv -O2 -Wall"). The > advice from the internet (stackoverflow) is exceedingly poor on this > question, in most cases addressing how to add flags, not how to change > the existing default flags. Alternatives like >OPT="" python3 ./setup.py > simply do not work. Not sure about setup.py, but `-g0` (after `-g`) should also disable debug information: +--- | Level 0 produces no debug information at all. Thus, -g0 negates -g. +--- Ansgar
overriding default compile flags when building python extensions
Dear Debian Python community, how does one control or override the default flags used by setup.py (setuptools module) when compiling a C extension for a python module? The intention is to switch off -g in pygalmesh, because of memory constraints on 32 bit systems when compiling against CGAL, see Bug#928140, https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=928140 A failed build, e.g. i386 at https://buildd.debian.org/status/fetch.php?pkg=pygalmesh=i386=0.3.1-1=1556128605=0 shows -g is used twice. The second usage comes from CFLAGS in dpkg-buildflags, which I can control. The first -g is the problem (in "-DNDEBUG -g -fwrapv -O2 -Wall"). The advice from the internet (stackoverflow) is exceedingly poor on this question, in most cases addressing how to add flags, not how to change the existing default flags. Alternatives like OPT="" python3 ./setup.py simply do not work. The default in question appears to be the OPT variable defined in /usr/lib/python3.7/config-3.7m-x86_64-linux-gnu/Makefile But how to override it? Upstream (Nico) suggests instead to build with CC=clang++. Is this a good alternative for Debian python modules? Drew
