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From: "oder at eleks dot lviv dot ua" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/27838] New: Wrong code generated for for()-loop with enumerated type as index Date: Wed, 31 May 2006 12:51:00 -0000 [thread overview] Message-ID: <bug-27838-12742@http.gcc.gnu.org/bugzilla/> (raw) I have enumerated type defined as follows enum EQUEUEDWRITERFILEERROR { QWFE__MIN, QWFE_REOPEN = QWFE__MIN, QWFE_WRITE, QWFE_OVERFLOW, QWFE__MAX, }; For it I have prefix increment operator defined with macro #define DEFINE_ENUM_INC_DEC(EnumType) \ static inline EnumType &operator ++(EnumType &Value) { return (EnumType &)(++((int &)Value)); } For following for-loop operator for (EQUEUEDWRITERFILEERROR qwfeError = QWFE__MIN; qwfeError != QWFE__MAX; ++qwfeError) compiler generated wrong code for condition check 0x8090981 mov 0xffffffd7(%ebp),%edx 0x8090984 mov 0xffffffd7(%ebp),%al 0x8090987 inc %edx 0x8090988 cmp $0x3,%al 0x809098a mov %edx,0xffffffd7(%ebp) 0x809098d jne 0x8090940 That is, variable is incremented in parallel with loop condition check and result of increment has effect to loop condition only on the next pass. This causes the loop to execute one time more than required. Compilation options used -malign-double -fshort-enums -freg-struct-return -fno-exceptions -g -O3 -march=pentium -fno-rtti -fconserve-space -- Summary: Wrong code generated for for()-loop with enumerated type as index Product: gcc Version: 3.3.5 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: oder at eleks dot lviv dot ua GCC build triplet: x86 GCC host triplet: x86 GCC target triplet: x86 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27838
next reply other threads:[~2006-05-31 12:51 UTC|newest] Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2006-05-31 12:51 oder at eleks dot lviv dot ua [this message] 2006-05-31 13:05 ` [Bug c++/27838] " schwab at suse dot de
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