On Sunday 20 November 2022 13:53:48 Pali Rohár wrote: > Hello! I would like to propose a new parameter for gcc: -mcrtdll= to > allow specifying against which Windows C Runtime library should be > binary linked. On Windows there are more crt libraries and currently gcc > links to libmsvcrt.a which is in most cases symlink to libmsvcrt-os.a > (but can be changed, e.g. during mingw-w64 building). mingw-w64 project > already builds import .a library for every crt dll library (from the old > crtdll.dll up to the new ucrtbase.dll), so it is ready for usage. Simple > patch for gcc which implements -mcrtdll parameter is below. Note that on > internet are other very similar patches for -mcrtdll= parameters and > some are parts of custom mingw32 / mingw-w64 gcc builds. What do you > think? Could gcc have "official" support for -mcrtdll= parameter?
Hello! I would like to ask gcc people, what do you think about such proposed -mcrtdll= parameter? There are lot of unofficial gcc patches which implement this -mcrtdll= parameter and this parameter is present in more gcc forks. So it looks like that this parameter is useful for more people. Here is list of some URLs which I found: https://sourceforge.net/p/mingw/mailman/message/5692227/ https://sourceforge.net/p/mingw-w64/mailman/message/36030107/ https://github.com/jmeubank/tdm-gcc-src/blob/tdm-patches.public/_PATCHES/mcrtdll.patch https://github.com/msys2/MINGW-packages/blob/master/mingw-w64-gcc/0006-Windows-New-feature-to-allow-overriding.patch https://github.com/nak5124/build_env/blob/master/gcc_build/patches/gcc/0020-MinGW-w64-Define-__MSVCRT_VERSION__.patch But I have not found any discussion about it on gcc mailing list. > > --- gcc/config/i386/cygming.opt 2022-02-06 21:00:05.377656896 +0100 > +++ gcc/config/i386/cygming.opt 2022-02-06 21:04:06.690995944 +0100 > @@ -22,6 +22,10 @@ mconsole > Target RejectNegative > Create console application. > > +mcrtdll= > +Target RejectNegative Joined > +Link with specified C RunTime DLL library. > + > mdll > Target RejectNegative > Generate code for a DLL. > --- gcc/config/i386/mingw32.h 2022-01-16 17:28:31.157999097 +0100 > +++ gcc/config/i386/mingw32.h 2022-01-16 17:36:03.552856726 +0100 > @@ -95,7 +95,20 @@ along with GCC; see the file COPYING3. > #undef CPP_SPEC > #define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{mthreads:-D_MT} " \ > "%{" SPEC_PTHREAD1 ":-D_REENTRANT} " \ > - "%{" SPEC_PTHREAD2 ": } " > + "%{" SPEC_PTHREAD2 ": } " \ > + "%{mcrtdll=crtdll*:-U__MSVCRT__ -D__CRTDLL__} " \ > + "%{mcrtdll=msvcrt10*:-D__MSVCRT_VERSION__=0x100} " \ > + "%{mcrtdll=msvcrt20*:-D__MSVCRT_VERSION__=0x200} " \ > + "%{mcrtdll=msvcrt40*:-D__MSVCRT_VERSION__=0x400} " \ > + "%{mcrtdll=msvcrt-os*:-D__MSVCRT_VERSION__=0x700} " \ > + "%{mcrtdll=msvcr70*:-D__MSVCRT_VERSION__=0x700} " \ > + "%{mcrtdll=msvcr71*:-D__MSVCRT_VERSION__=0x701} " \ > + "%{mcrtdll=msvcr80*:-D__MSVCRT_VERSION__=0x800} " \ > + "%{mcrtdll=msvcr90*:-D__MSVCRT_VERSION__=0x900} " \ > + "%{mcrtdll=msvcr100*:-D__MSVCRT_VERSION__=0xA00} " \ > + "%{mcrtdll=msvcr110*:-D__MSVCRT_VERSION__=0xB00} " \ > + "%{mcrtdll=msvcr120*:-D__MSVCRT_VERSION__=0xC00} " \ > + "%{mcrtdll=ucrt*:-D_UCRT} " > > /* For Windows applications, include more libraries, but always include > kernel32. */ > @@ -185,11 +198,16 @@ along with GCC; see the file COPYING3. > #define REAL_LIBGCC_SPEC \ > "%{mthreads:-lmingwthrd} -lmingw32 \ > " SHARED_LIBGCC_SPEC " \ > - -lmoldname -lmingwex -lmsvcrt -lkernel32" > + -lmoldname -lmingwex %{!mcrtdll=*:-lmsvcrt} %{mcrtdll=*:-l%*} -lkernel32" > > #undef STARTFILE_SPEC > -#define STARTFILE_SPEC "%{shared|mdll:dllcrt2%O%s} \ > - %{!shared:%{!mdll:crt2%O%s}} %{pg:gcrt2%O%s} \ > +#define STARTFILE_SPEC " \ > + %{shared|mdll:%{mcrtdll=crtdll*:dllcrt1%O%s}} \ > + %{shared|mdll:%{!mcrtdll=crtdll*:dllcrt2%O%s}} \ > + %{!shared:%{!mdll:%{mcrtdll=crtdll*:crt1%O%s}}} \ > + %{!shared:%{!mdll:%{!mcrtdll=crtdll*:crt2%O%s}}} \ > + %{pg:%{mcrtdll=crtdll*:gcrt1%O%s}} \ > + %{pg:%{!mcrtdll=crtdll*:gcrt2%O%s}} \ > crtbegin.o%s \ > %{fvtable-verify=none:%s; \ > fvtable-verify=preinit:vtv_start.o%s; \ >
