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--></style></head><body lang=EN-CA link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have a question regarding the following example. <o:p></o:p></p><p class=MsoNormal><a href="https://www.mcs.anl.gov/petsc/petsc-current/src/ksp/ksp/tutorials/ex14f.F90.html">https://www.mcs.anl.gov/petsc/petsc-current/src/ksp/ksp/tutorials/ex14f.F90.html</a><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=p1>When debug flags are used in the make file, the code crashed with following error.<o:p></o:p></p><p class=p1><o:p> </o:p></p><p class=p1>At line 335 of file ex14f.F90<o:p></o:p></p><p class=MsoNormal><span style='font-size:8.5pt;font-family:Menlo;color:black'>Fortran runtime error: Index '-14450582413' of dimension 1 of array 'xx' below lower bound of 1<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=p1><span class=s1>FFLAGS</span><span class=s2> </span><span class=apple-converted-space> </span><span class=s2>= -g -fcheck=all -fbacktrace -Wall</span><o:p></o:p></p><p class=p1><span class=s1>CPPFLAGS</span><span class=s2> </span><span class=apple-converted-space> </span><span class=s2>= -g -fcheck=all -fbacktrace -Wall<o:p></o:p></span></p><p class=p1><span class=s2><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>Does this make sense?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>Danyang<o:p></o:p></span></p></div></body></html>