<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I think this problem ultimately stems from the fact that gcc/g++ and gfortran are not from the same people on macOS. It seems like clang is configured to build for 11.0 target, whilst gcc defaults to newest available target. And indeed if I change my compile command there is no warning:<div class=""><br class=""></div><div class="">mkdir -p build && gfortran -c -o ./build/conftest.o conftest.F90 && gcc-10 -o ./build/libconftest.dylib ./build/conftest.o -dynamiclib -undefined dynamic_lookup && rm -rf ./build<br class=""><div class=""><br class=""></div><div class="">Note I now call gcc-10 as the linker which is the __actual__ gcc (not clang in a trench coat).</div><div class=""><br class=""></div><div class=""><div class="">
<div dir="auto" style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div>Best regards,<br class=""><br class="">Jacob Faibussowitsch<br class="">(Jacob Fai - booss - oh - vitch)<br class="">Cell: (312) 694-3391</div></div>
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<div><br class=""><blockquote type="cite" class=""><div class="">On Feb 15, 2021, at 11:46, Jacob Faibussowitsch <<a href="mailto:jacob.fai@gmail.com" class="">jacob.fai@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Ok so if I pass -mmacosx-version-min=11.2 to the linker the warning disappears...<div class=""><br class=""></div><div class=""><div class="">
<div dir="auto" style="caret-color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class="">Best regards,<br class=""><br class="">Jacob Faibussowitsch<br class="">(Jacob Fai - booss - oh - vitch)<br class="">Cell: (312) 694-3391</div></div>
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<div class=""><br class=""><blockquote type="cite" class=""><div class="">On Feb 15, 2021, at 11:41, Jacob Faibussowitsch <<a href="mailto:jacob.fai@gmail.com" class="">jacob.fai@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I can reproduce the warning compiling just that simple code you listed. This is the compile command:<div class=""><br class=""></div><div class="">mkdir -p build && gfortran -c -o ./build/conftest.o conftest.F90 && gcc -o ./build/libconftest.dylib ./build/conftest.o -dynamiclib -undefined dynamic_lookup && rm -rf ./build</div><div class=""><br class=""></div><div class="">And error:</div><div class="">ld: warning: object file (./build/conftest.o) was built for newer macOS version (11.2) than being linked (11.0)</div><div class=""><br class=""></div><div class="">Note I recently uninstalled and reinstalled command line tools too, which does not seem to have fixed it.</div><div class=""><br class=""></div><div class=""><div class=""><div class="">
<div dir="auto" style="caret-color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class="">Best regards,<br class=""><br class="">Jacob Faibussowitsch<br class="">(Jacob Fai - booss - oh - vitch)<br class="">Cell: (312) 694-3391</div></div>
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<div class=""><br class=""><blockquote type="cite" class=""><div class="">On Feb 15, 2021, at 11:30, Satish Balay <<a href="mailto:balay@mcs.anl.gov" class="">balay@mcs.anl.gov</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">Here is the compile command and the warning:<br class=""><br class=""><blockquote type="cite" class=""><blockquote type="cite" class=""><blockquote type="cite" class=""><blockquote type="cite" class=""><blockquote type="cite" class=""><blockquote type="cite" class=""><br class=""></blockquote></blockquote></blockquote></blockquote></blockquote></blockquote>===== Checking linker<br class="">Executing: gfortran -c -o /var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers/conftest.o -I/var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers /var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers/conftest.F90 <br class="">Successful compile:<br class="">Source:<br class=""> function foo(a)<br class=""> real:: a,x,bar<br class=""> common /xx/ x<br class=""> x=a<br class=""> foo = bar(x)<br class=""> end<br class="">Executing: gcc -o /var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers/libconftest.dylib -dynamiclib -single_module -undefined dynamic_lookup -multiply_defined suppress /var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers/conftest.o <br class="">Possible ERROR while running linker:<br class="">stderr:<br class="">ld: warning: object file (/var/folders/9w/7dlszmmn6q1gd5yf3r9n79bc0000gn/T/petsc-dk9aiv7x/config.setCompilers/conftest.o) was built for newer macOS version (11.2) than being linked (11.0)<br class=""> Accepted FC PIC code without compiler flag<br class=""> =============================================================================================<br class=""><<<<<<<br class=""><br class="">Its likely due to the way brew built gfortran. You can try compiling a simple test code and see if you can reproduce this warning.<br class=""><br class="">There is a related issue at:<br class=""><br class=""><a href="https://github.com/spack/spack/issues/21644" class="">https://github.com/spack/spack/issues/21644</a><br class=""><br class="">Satish<br class=""><br class=""><br class="">On Sat, 13 Feb 2021, Jacob Faibussowitsch wrote:<br class=""><br class=""><blockquote type="cite" class="">Hello All,<br class=""><br class="">I’ve been getting these warnings for weeks, at first I figured it was due to gfortran brew package not being updated for Big Sur, but since it has persisted through a few gfortran brew updates I’m thinking it may be petsc related. This is on clean build on master.<br class=""><br class="">ld: warning: object file (master-arch-darwin-c-debug/obj/sys/classes/bag/f2003-src/fsrc/bagenum.o) was built for newer macOS version (11.2) than being linked (11.0)<br class="">ld: warning: object file (master-arch-darwin-c-debug/obj/sys/f90-src/fsrc/f90_fwrap.o) was built for newer macOS version (11.2) than being linked (11.0)<br class="">ld: warning: object file (master-arch-darwin-c-debug/obj/sys/objects/f2003-src/fsrc/optionenum.o) was built for newer macOS version (11.2) than being linked (11.0)<br class="">ld: warning: object file (master-arch-darwin-c-debug/obj/sys/fsrc/somefort.o) was built for newer macOS version (11.2) than being linked (11.0)<br class="">ld: warning: object file (master-arch-darwin-c-debug/obj/sys/f90-mod/petscsysmod.o) was built for newer macOS version (11.2) than being linked (11.0)<br class=""><br class="">Best regards,<br class=""><br class="">Jacob Faibussowitsch<br class="">(Jacob Fai - booss - oh - vitch)<br class="">Cell: (312) 694-3391<br class=""><br class=""></blockquote></div></div></blockquote></div><br class=""></div></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div><br class=""></div></div></body></html>