lib/coproc.h:230:46: clearing an object of non-trivial type ‘struct PCI_INFO’; use assignment or value-initialization instead [-Wclass-memaccess]

[smoe]

Hello,
I just backported 7.16.1 and saw myriads of the following compiler warning.
Cheers,
Steffen

/usr/local/bin/g++ -DHAVE_CONFIG_H -I. -I..  -I.. -I../api -I../db -I../lib -I../lib/mac -I../sched -I../tools -I../vda -pthread -I/usr/include/mariadb -I/usr/include/mariadb/mysql -pthread -Wdate-time -D_FORTIFY_SOURCE=2  -Wall -Wextra -Wshadow -Wredundant-decls -Wdisabled-optimization -Wpointer-arith -Wstrict-aliasing -Wcast-align  -g -O2 -fdebug-prefix-map=/home/moeller/boinc/boinc-7.16.1+dfsg=. -fstack-protector-strong -Wformat -Werror=format-security -Wall -O3 -funroll-loops -fforce-addr -ffast-math -flto -Wall -c -o sample_bitwise_validator.o sample_bitwise_validator.cpp
In file included from ../lib/hostinfo.h:32,
                 from sched_limit.h:25,
                 from sched_config.h:25,
                 from validator.h:18,
                 from sample_bitwise_validator.cpp:35:
../lib/coproc.h: In member function ‘void COPROC::clear()’:
../lib/coproc.h:230:46: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘struct PCI_INFO’; use assignment or value-initialization instead [-Wclass-memaccess]
         memset(&pci_info, 0, sizeof(pci_info));
                                              ^
../lib/coproc.h:133:8: note: ‘struct PCI_INFO’ declared here
 struct PCI_INFO {
        ^~~~~~~~

[smoe]

Ah - same here:

In file included from ../lib/gui_rpc_client.h:52,
                 from screensaver_x11.cpp:41:
../lib/prefs.h: In member function ‘void WEEK_PREFS::clear()’:
../lib/prefs.h:108:43: warning: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘struct WEEK_PREFS’; use assignment or value-initialization instead [-Wclass-memaccess]
         memset(this, 0, sizeof(WEEK_PREFS));
                                           ^
../lib/prefs.h:104:8: note: ‘struct WEEK_PREFS’ declared here
 struct WEEK_PREFS {
        ^~~~~~~~~~

[AenBleidd]

Do you have some time to invest it to fix these warnings?

[smoe]

Not today - was only "quickly" procastinating into rolling 7.16.1 on one of my machines. Will address them over the weekend.

[oppiet30]

There is a lot more than just that one.
boinc_compile_warnings.txt

[oppiet30]

Oppie> It's telling you the class is not a plain-old C struct anymore because
you added a constructor. So memset could blow-away your class's data. There
are lots of valid ways to deal with this, including just ignoring the warning.
In general, memset is wrong. But C coders can't let it go. Anyway, here's the
fix:

// bad
memset(&pci_info, 0, sizeof(pci_info));

// good
pci_info = PCI_INFO{};

[AenBleidd]

Fixed via #3364