[Bug libstdc++/77726] New: On MinGW targets, user-defined `operator delete(void *)` is not called if the sized-deallocation version is not provided in C++14 mode when libstdc++ is linked dynamically

[lh_mouse at 126 dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77726

            Bug ID: 77726
           Summary: On MinGW targets, user-defined `operator delete(void
                    *)` is not called if the sized-deallocation version is
                    not provided in C++14 mode when libstdc++ is linked
                    dynamically
           Product: gcc
           Version: 6.2.1
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: lh_mouse at 126 dot com
  Target Milestone: ---

Testcase:



E:\Desktop>cat test.cc
void *operator new(__SIZE_TYPE__ cb){
        auto p = __builtin_malloc(cb);
        __builtin_printf("%s: %p\n", __PRETTY_FUNCTION__, p);
        return p;
}
void operator delete(void *p) noexcept {
        __builtin_printf("%s: %p\n", __PRETTY_FUNCTION__, p);
        __builtin_free(p);
}
#if 0
void operator delete(void *p, __SIZE_TYPE__ cb) noexcept {
        __builtin_printf("%s: %p, %lu\n", __PRETTY_FUNCTION__, p, (unsigned
long)cb);
        __builtin_free(p);
}
#endif
int main(){
        delete new int;
}

E:\Desktop>g++ test.cc -std=c++14 -Wall -Wextra -pedantic
test.cc:6:6: warning: the program should also define 'void operator
delete(void*, unsigned int)' [-Wsized-deallocation]
 void operator delete(void *p) noexcept {
      ^~~~~~~~

E:\Desktop>a.exe
void* operator new(unsigned int): 003F6FA0

E:\Desktop>g++ test.cc -std=c++14 -Wall -Wextra -pedantic -static
test.cc:6:6: warning: the program should also define 'void operator
delete(void*, unsigned int)' [-Wsized-deallocation]
 void operator delete(void *p) noexcept {
      ^~~~~~~~

E:\Desktop>a.exe
void* operator new(unsigned int): 007C6CF8
void operator delete(void*): 007C6CF8

E:\Desktop>g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=C:/MinGW/MSYS2/mingw32/lib/gcc/i686-w64-mingw32/6.2.1/lto-wrapper.exe
Target: i686-w64-mingw32
Configured with: ../gcc/configure --prefix=/mingw32
--with-local-prefix=/mingw32/local --build=i686-w64-mingw32
--host=i686-w64-mingw32 --target=i686-w64-mingw32
--with-native-system-header-dir=/mingw
32/i686-w64-mingw32/include --libexecdir=/mingw32/lib --enable-bootstrap
--with-arch=i686 --with-tune=generic --enable-languages=c,lto,c++
--enable-shared --enable-static --enable-libatomic --enable-t
hreads=mcf --enable-graphite --enable-fully-dynamic-string
--enable-libstdcxx-time=yes --disable-libstdcxx-pch --disable-libstdcxx-debug
--disable-isl-version-check --enable-lto --enable-libgomp --dis
able-multilib --enable-checking=release --disable-rpath
--disable-win32-registry --disable-nls --disable-werror --disable-symvers
--with-libiconv --with-system-zlib --with-gmp=/mingw32 --with-mpfr=/mi
ngw32 --with-mpc=/mingw32 --with-isl=/mingw32 --with-pkgversion='gcc-6-branch
HEAD with MCF thread model, built by LH_Mouse.'
--with-bugurl=http://github.lhmouse.com/ --with-gnu-as --with-gnu-ld --dis
able-tls --disable-sjlj-exceptions --with-dwarf2
Thread model: mcf
gcc version 6.2.1 20160924 (gcc-6-branch HEAD with MCF thread model, built by
LH_Mouse.)