<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><br class=""></div> This happens when the module files were created with one Fortran compiler, say ifort`, but it is attempting to read them with a different Fortran compiler, say gfortran. (You can never mix to different Fortran compilers in the same executable/library/module system.<div class=""><br class=""></div><div class=""> You need to use a different PETSC_ARCH and configure PETSc with --with-fc=gfortran to use the gfortran compiler</div><div class=""><br class=""></div><div class=""> Barry</div><div class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Sep 6, 2022, at 11:59 AM, Han Tran <<a href="mailto:tranduchan@gmail.com" class="">tranduchan@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">I used to compile my Fortran 90 code using intel compilers (i.e. intel and impi). However, when I tried to compile using gcc, it gave the following error.</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> use petscksp</span></div><div style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> 1</span></div><div style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Fatal Error: File 'petscksp.mod' opened at (1) is not a GNU Fortran module file</span></div></div><div class=""><br class=""></div><div class="">It would be appreciated if you could give any hints on this issue. Thank you so much!</div><div class=""><br class=""></div><div class="">-Han</div></div></div></blockquote></div><br class=""></div></body></html>