[Bug middle-end/46597] New: configure -enable-checking=... -enable-build-with-cxx and bootstrap is g++ 3.3 hit minor problem

[Bug middle-end/46597] New: configure -enable-checking=... -enable-build-with-cxx and bootstrap is g++ 3.3 hit minor problem

[jay.krell at cornell dot edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46597

           Summary: configure -enable-checking=... -enable-build-with-cxx
                    and bootstrap is g++ 3.3 hit minor problem
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jay.krell@cornell.edu


I hit an error using g++ 3.3 to bootstrap on Darwin/ppc and configure
-enable-build-with-cxx -enable-checking=...

../../gcc-4.5/gcc/alias.c: In function `rtx_def* find_base_value(rtx_def*)':
../../gcc-4.5/gcc/alias.c:1008: error: cannot convert `rtx_def*' to `const 

    case PLUS:
    case MINUS:
      {
    rtx temp, src_0 = XEXP (src, 0), src_1 = XEXP (src, 1); <== this line 


I suggest therefore rtl.h:


< #if defined ENABLE_RTL_FLAG_CHECKING && GCC_VERSION > 2007
> #if defined ENABLE_RTL_FLAG_CHECKING && ((!defined(__cplusplus) && GCC_VERSION > 2007) || GCC_VERSION > 3003)
#define RTL_FLAG_CHECK1(NAME, RTX, C1) __extension__            \


or even just:
> #if defined ENABLE_RTL_FLAG_CHECKING && GCC_VERSION > 3003


or like, not necessarily in rtl.h:

 #if GCC_VERSION <= 3003
 #undef ENABLE_RTL_FLAG_CHECKING


or

 #if GCC_VERSION <= 3003 && defined(__cplusplus)
 #undef ENABLE_RTL_FLAG_CHECKING

Some allowance might be made for other compilers that implement the extensions
though?
Or, in C++, maybe use extensions less? e.g. inline functions might suit?


Thanks,
 - Jay

[Bug middle-end/46597] configure -enable-checking=... -enable-build-with-cxx and bootstrap is g++ 3.3 hit minor problem

[jay.krell at cornell dot edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46597

--- Comment #1 from Jay <jay.krell at cornell dot edu> 2010-12-28 13:50:06 UTC ---
I put #define ENABLE_CHECKING_GCC_VERSION ((GCC_VERSION > 3003) ||
(!defined(__cplusplus) && (GCC_VERSION > 2007)))
 in include/ansidecl.h after #define GCC_VERSION and I && this with the #if
FOO_CHECKING in rtl.h, tree.h, ira-int.h.


Alternatively, reject g++ < 3.4 entirely, or if enable-checking.
Or, well, I'm using -disable-bootstrap, and probably checking is never enabled
in the first phase anyway, so this all would just work if I didn't use that.
The patch is ok, but it might never make a difference if I didn't
-disable-bootstrap.


But I really really really like -disable-bootstrap, given how little I build,
which is still a very useful amount, it saves a ton (just libbackend.a and a
small frontend, no libraries, and I patched out gmp/mpfr/mpc dependencies, so
overall build is short even on slower machines (we run a range of machines..)).

[Bug middle-end/46597] configure -enable-checking=... -enable-build-with-cxx and bootstrap is g++ 3.3 hit minor problem

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46597

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |WONTFIX

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
You cannot build GCC 11+ without C++11 support so this is a won't fix at this
point.