Fixes are available
APAR status
Closed as program error.
Error description
The following small test case demonstates that the xlf compiler have a bug in the evaluation of logical expressions: ... integer*4 x/1/, y/2000/ ... ((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) evaluates to true .not.((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) also comes out true. This issue affects XLF V12.1 and XLF V13.1. ===== TESTCASE: $cat test_case.f program IBM BROKEN FORTRAN integer*4 x/1/, y/2000/ c THIS EXPRESSION SHOULD EVALUATE TO TRUE write (*,*)' ((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x))' + , ((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) if (((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x))) then write (*,*) '-OK-: EVALUATES TO TRUE' end if c THIS EXPRESSION SHOULD EVALUATE TO FALSE write (*,*)'.not.((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x))' + , .not.((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) c ON IBM, IT ERRONEOUSLY EVALUATES TO TRUE if (.not.((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x))) then write (*,*) '*ERROR*: EVALUATES TO TRUE' else write (*,*) '-OK-: EVALUATES TO FALSE' end if end ===== COMPILE COMMAND: xlf test_case.f $./a.out ((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) T -OK-: EVALUATES TO TRUE .not.((.not.((x.eq.1).and.(y.lt.1000))).and.(1.eq.x)) T *ERROR*: EVALUATES TO TRUE
Local fix
N/A
Problem summary
PROBLEM DESCRIPTION: Certain combinations of negated short-circuit expressions were evaluated incorrectly. USERS AFFECTED: Users that depend on short-circuit evaluation.
Problem conclusion
Problem is fixed in the short-circuit expression generator. Apply recommended PTF.
Temporary fix
Comments
APAR Information
APAR number
LI76239
Reported component name
XL FORTRAN RHEL
Reported component ID
5724U8410
Reported release
C10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2011-06-10
Closed date
2011-06-10
Last modified date
2011-06-10
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
XL FORTRAN RHEL
Fixed component ID
5724U8410
Applicable component levels
RC10 PSN IZ89350
UP06/09/13
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Document Information
Modified date:
24 February 2022