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D - [BUG] dmd segfaults on sdl_syswm.d

reply "Christian Schüler" <leichenzehrer alpenjodel.de> writes:
Hi Walter,

Using the SDL version currently available from the DedicateD page, and DMD
version 0.79, I get a segfault. The module which causes trouble is
sdl_syswm.d. If I comment out this module from beeing imported, no crash
happens. An empty application importing sdl.d is sufficient to reproduce the
bug. More specifically:

import sdl.d --> import sdl_events.d --> import sys_syswm.d --> crash


PS:
Thumbs up for the continuing improvements on D! Templates and operator
overloading hasn't been there the last time I checked D, which must have
been early 2002.

I also tried to write a litte vector3-struct with the new operator
overloading and checked the asm-output of the compiler (it's kind of a thing
I try with every new compiler I get my hands on).

Result 1:
I found out that the current D compiler doens't care much about the -O
switch and inlining option. This is ok, it's not an 1.0 version after all.

Result 2:
I was surprised to see the "movsd" instruction is used to copy values
around. I'm surprised because it's said to be deprecated and this is
probably a general code-generation feature of your backend and not releated
to D alone. Example:


struct vector3
{
   float x, y, z;
   vector3 opPlus( const vector3 &other )
   { vector3 result; result.x = x + other.x; .... ; return result; }
}

vector3 A, B, C;
A = B + C;

The asm of opPlus() with -O is structured like this, correct me if I'm wrong

   prolog
   mov edi, & result
   mov esi, & (default-initializer object ?)
   movsd
   movsd
   movsd
   floating point oprations
   mov edi, &A
   mov esi, &result
   movsd
   movsd
   movsd
   epilog
   ret

Besides there beeing a redundant copy and the whole function not beeing
inlined, the asm makes use of the string instruction "movsd". It is believed
that string instructions and other complex instructions (bit-scans for
instance) don't translate well to modern processor's microcode and are
deprecated in favor of writing more risc-like code. So you should do
instead:

   mov edi, &A
   mov esi, &result
   mov eax, dword ptr [esi]
   mov dword ptr [edi], eax
   mov eax, dword ptr [esi+8]
   mov dword ptr [edi+8], eax
   mov eax, dword ptr [esi+16]
   mov dword ptr [edi+16], eax

Is anybody able to confirm this? (For the record, GCC does produce risc-like
output)

Greetings
Christian
Jan 25 2004
next sibling parent yaneurao <yaneurao_member pathlink.com> writes:
In article <bv2cm8$29of$1 digitaldaemon.com>, Ch
prev sibling parent reply "Walter" <walter digitalmars.com> writes:
"Ch
parent reply "Christian Schüler" <leichenzehrer alpenjodel.de> writes:
Hi Walter,
here you are (see attachment)

----------------------------------

import sdl_syswm;

int main()
{
    return 0;
}

----------------------------------

- importing sdl_version doesn't crash
- replicating the code of sdl_syswm into the main file doesn't crash
- renaming sdl_version to sdl_ver doesn't crash

hope this helps



"Walter" <walter digitalmars.com> schrieb im Newsbeitrag
news:bv3n4g$1g6v$1 digitaldaemon.com...

 Can you please cut it down to a minimum example and post it / email it to
 me? Thanks.
begin 666 SDL_syswm.zip M4$L#!!0````(`*B1.S"O)HT:,00``*H(```+````4T1,7W-Y<W=M+F2E55MO M(C<4?L[\BI-]28((ET35-N6E;$(2)""( 2*>*C-C&"L>&]D>V%'5_]YS[!D MJVREJCR,P'.NW\6T&Q' )WX:P2W$(M])#D_"\,2->2H8C%C)C0]YU+O2B&WF MX/KQ!KH/#U^;]/S5/Q^:<-?I=/RSB^58CIG*";5ED<^>9\*"%&O#3 GX=6,X M!ZLW[L ,[T&I"TB8`H--K3-B73 .P %3:5N'_KE.Q::DPT*EW(#+.#AN< MZ MXW^\3!8PJCJ\<,4-DS MUE(D/G\D$JXL!V9A1Z<VXRFL2Y_Z3-/$U33PK+$# M<T*K'G"![\,`>VXLGL%=W;"JV 1MX)HY6L* WE'B#4Y> F0X8)W7^AR(T[XI M".7K9GJ'JV58$9<]""EAS:&P?%/(IJ^!T; <SE_?%G/H3U:P[,]F_<E\U<-H MEVE\R_<\U")&!9;&Q0P24N+LOL1X,'M\Q9S^M^%H.%_1"L_#^600Q_#\-H,^ M3/NS^?!Q,>K/8+J83=_B00MYY;R&NL+T,[B/4&^P:JX1T90[)J2M(% AV1;' ME"ED;,^1](2+/0[)($&1_5<^I59;OSAFG;#M =B TJX)!R-03$X?F?;I)Y*; M,%1)JPF_/,"<>P-,)4N0UKB Q/M[E/4W;1U%COL`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`E67'PQ)I0S'5/1P MERY'*G><D;Q&=U_.J2CZ<+A!2UU9ND+/W]"?'56BY!KIG.=KG+NZMJM)3H-2 M:;5'SV RNK2>H=."B! C%Q%O+]PMQT/,O?Y(:X.>-[WH'U!+`P04````" !R MG;LLJ#['^B $``#6" ``#0```%-$3%]V97)S:6]N+F2556UOXC 0_MS\BM%* M)P&;4EYTVFU15Y>E=,N)`H+0+?U2F60HOG5LY#CTT.G^^XV=A)<6K?802IQX M9OS,,\],+FH>T&]Z,X!SF/)D+1!NN,;(W&/,&0S8%K4SZ:KU5O.7E8%*MPK- MR\M/OKU^=M=+'UJ-1L-=FQ2.)>0I#9<OS'/>X8JG(/A",[T%6BXU(J1J:5Z9 MQ YL5081DZ#IT-1HOL ,`C? 9'RA\O,3%?/EUK[,9(P:S K!H$Y24$OW\&TX M T%QPC>4J)F <;80/'+^`QZA3!%8"FO[-EUA#(NM<[VU:*8%&KA5= (S7,D. M(*?]', &=4KOH%4>6$3T06FH,&.3T*#6UK%*R+< & $L_>JGB=CG&P.7+NY* MK2FU%46D9%^Y$+! R%)<9L)W,< :OO?#N]$LA& XA^_!9!(,PWF'K,U*T2YN M,(]E*\HI-"6FJ2!;PNY"W/<FW3OR";[V!_UP;E.X[8?#WG0*MZ,)!# .)F&_ M.QL$$QC/)N/1M%>GNB*65!><GJ)[1_62HB:*&(W1,"[2 H(Y%3LEF"*&%=L M%3U"OB&0#"(2V?^MIU#RQ25.7GMN.\"7()7QX55S$I-1NTH[]WV1?>C+J.[# M[Y<0HFN L6 1E76:6<=VFV3]5:7&6MX'`(U6L]D\;[8;GP!FTR#/Z4CQ]D4J M5/8#Y1\Q;I3([#GU2"5>[<+S+FJY"E;(K)!C7'*)J8,795JC-*X?2[U9%RJC MTN[UL]FN,>UX'OY-XI+4BU<NXEAS:=A".-839J[ PV]QW?T_6-Q_CB9TZP_M M;1R$W;M![Z$WL' B)5-J*IX?^^Q,GQ]ZDVE_-#R[AF;GG86-<F#1>F>Q/^", M]MN$ED2>1?EFF=<_WMF,'#Y#POY2NK-[XO+ :<U,M.IX_^Y92UBDE1L6>5?$ MMK1+VR5L1UE^6D;**W1!S*IDS06>&YZ0`&H[TT)LEO!".77/4KY1/'9PBSPK M!]!K\%CU"/YCW4&'Z_?$==RN3:7</23-[;K4BMT]82=RI41D+H\2M,R2!2UI M8%#NS#ZBIK[;,)'AE95?I>FW_'85SK_0LM5H5[UR]+ T)>LTGR]VMF$^8B2- M#&TI=0U+NQ*:C4;.OZ ]D5JM["I<)#*<W5?R0CWZD"_FY>+)<:31PH='HISB M-> CS/,EK9Z.DN6G<BPHL)/D)_WQ1G[=T?VX/^C=%"!/U6<'QSLK?^^J5.(\ M-CDLU9M".2+15H$5$T=G:.=0(;XXEZ,%3^0+9 3ZL3ZO/]D<%OR(V>< '/2" M:?AK]%9.I?WE^FVI* KY/U6K1\0O,QG9`04O:(YK4#1'O)4LX1$3 KYI7/[ M^$V_ /U2%2-]. I_I3-]$F]J: *Z;W_N:P.17]F0SP^Y4Z6:\YLWYN$(J3FS M 8.TM^YX_P%02P$"% L4````" "HD3LPKR:-&C$$``"J" ``"P`````````! M`" ` ($`````4T1,7W-Y<W=M+F102P$"% L4````" !RG;LLJ#['^B $``#6 M" ``#0`````````!`" ` (%:! ``4T1,7W9E<G-I;VXN9%!+!08`````` `" +`'0```"E" `````` ` end
Jan 27 2004
parent reply ahiru <ahiru moephp.org> writes:
In article <bv66ih$2ivd$1 digitaldaemon.com>, Ch
parent reply "Christian Schüler" <leichenzehrer alpenjodel.de> writes:
Is this going to be fixed in the future?
Or must we assume that struct names equalling module names are not going to
be accepted by the compiler?


"ahiru" <ahiru moephp.org> schrieb im Newsbeitrag
news:bv699a$2nk9$1 digitaldaemon.com...
 In article <bv66ih$2ivd$1 digitaldaemon.com>, Ch
parent reply "C" <dont respond.com> writes:
I never understood why that was , it seems naturall to me to write module
myClass; \n\n class myClass { } ... .  Could we get this ?

C
"Ch
next sibling parent yaneurao <yaneurao_member pathlink.com> writes:
In article <bv9343$1ch1$1 digitaldaemon.com>, C says...
I never understood why that was , it seems naturall to me to write module
myClass; \n\n class myClass { } ... .  Could we get this ?
of course , you are right. this may be a bug , a pity it doesn't occur in Mr.Walter's environment. cf. D/21886 yaneurao.
Jan 28 2004
prev sibling parent reply J C Calvarese <jcc7 cox.net> writes:
C wrote:
 I never understood why that was , it seems naturall to me to write module
 myClass; \n\n class myClass { } ... .  Could we get this ? 
I haven't been following this thread particularly closely, but I think we can do this. Both of the examples I attached work for me. Does it fail when the example is more complicated (such was with importing)? This sounds like it might be a bug. -- Justin http://jcc_7.tripod.com/d/
Jan 28 2004
parent reply "Christian Schüler" <leichenzehrer alpenjodel.de> writes:
Hi JC
As I pointed out, the crashed only if the offending instruction was "2
modules deep".

import sdl --> import sdl_syswm --> implort sdl_version

if instead

import sdl_version

no crash happened

-chris


"J C Calvarese" <jcc7 cox.net> schrieb im Newsbeitrag
news:bv9jac$28qb$1 digitaldaemon.com...
 C wrote:
 I never understood why that was , it seems naturall to me to write
module
 myClass; \n\n class myClass { } ... .  Could we get this ?
I haven't been following this thread particularly closely, but I think we can do this. Both of the examples I attached work for me. Does it fail when the example is more complicated (such was with importing)? This sounds like it might be a bug. -- Justin http://jcc_7.tripod.com/d/
---------------------------------------------------------------------------- ----
 module mod;

 import std.c.stdio;

 struct mod
 {
 int whatever;
 }


 void main()
 {
 mod myMod;

 myMod.whatever = 1692;

 //mod myMod = new mod();
 printf("It works.\n");
 }
---------------------------------------------------------------------------- ----
 module mod;

 import std.c.stdio;

 class mod
 {
 int whatever;

 this()
 {
 printf("Ok.  Let's go.\n");
 }
 }


 void main()
 {
 mod myMod = new mod();
 printf("It works.\n");
 }
Feb 02 2004
parent J C Calvarese <jcc7 cox.net> writes:
Ch