On Feb 15, 2021, at 12:05, Satish Balay <balay@mcs.anl.gov> wrote:

Does setting MACOSX_DEPLOYMENT_TARGET also work?

Satish

On Mon, 15 Feb 2021, Jacob Faibussowitsch wrote:

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:

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

Note I now call gcc-10 as the linker which is the __actual__ gcc (not clang in a trench coat).

Best regards,

Jacob Faibussowitsch
(Jacob Fai - booss - oh - vitch)
Cell: (312) 694-3391

On Feb 15, 2021, at 11:46, Jacob Faibussowitsch <jacob.fai@gmail.com> wrote:

Ok so if I pass -mmacosx-version-min=11.2 to the linker the warning disappears...

Best regards,

Jacob Faibussowitsch
(Jacob Fai - booss - oh - vitch)
Cell: (312) 694-3391

On Feb 15, 2021, at 11:41, Jacob Faibussowitsch <jacob.fai@gmail.com <mailto:jacob.fai@gmail.com>> wrote:

I can reproduce the warning compiling just that simple code you listed. This is the compile command:

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

And error:
ld: warning: object file (./build/conftest.o) was built for newer macOS version (11.2) than being linked (11.0)

Note I recently uninstalled and reinstalled command line tools too, which does not seem to have fixed it.

Best regards,

Jacob Faibussowitsch
(Jacob Fai - booss - oh - vitch)
Cell: (312) 694-3391

On Feb 15, 2021, at 11:30, Satish Balay <balay@mcs.anl.gov <mailto:balay@mcs.anl.gov>> wrote:

Here is the compile command and the warning:

===== Checking linker
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 
Successful compile:
Source:
    function foo(a)
    real:: a,x,bar
    common /xx/ x
    x=a
    foo = bar(x)
    end
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 
Possible ERROR while running linker:
stderr:
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)
        Accepted FC PIC code without compiler flag
        =============================================================================================
<<<<<<

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.

There is a related issue at:

https://github.com/spack/spack/issues/21644 <https://github.com/spack/spack/issues/21644>

Satish


On Sat, 13 Feb 2021, Jacob Faibussowitsch wrote:

Hello All,

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.

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)
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)
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)
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)
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)

Best regards,

Jacob Faibussowitsch
(Jacob Fai - booss - oh - vitch)
Cell: (312) 694-3391