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>>>>> -static volatile const __u32 ret1; >>>>> +volatile const __u32 print_len = 0; >>>>> +volatile const __u32 ret1 = 0; >>>> >>>> I am little bit puzzled why bpf_iter_test_kern4.c is impacted. I think >>>> this is not in a static link test, right? The same for a few tests below. >>> >>> All the selftests are passed through a static linker, so it will >>> append obj_name to each static variable. So I just minimized use of >>> static variables to avoid too much code churn. If this variable was >>> static, it would have to be accessed as >>> skel->rodata->bpf_iter_test_kern4__print_len, for example. >> >> Okay this should be fine. selftests/bpf specific. I just feel that >> some people may get confused if they write/see a single program in >> selftest and they have to use obj_varname format and thinking this >> is a new standard, but actually it is due to static linking buried >> in Makefile. Maybe add a note in selftests/README.rst so we >> can point to people if there is confusion. > > I'm not sure I understand. > Are you saying that > bpftool gen object out_file.o in_file.o > is no longer equivalent to llvm-strip ? This is more about BTF and ELF. Give a simple example, $ cat t1.c volatile static int aa = 10; int foo() { return aa; } $ clang -O2 -g -c -target bpf t1.c Using bpftool compiled with this patch: $ bpftool gen object output.o t1.o $ llvm-readelf -s t1.o | grep aa 3: 0000000000000000 4 OBJECT LOCAL DEFAULT 4 aa $ llvm-readelf -s output.o | grep aa 3: 0000000000000000 4 OBJECT LOCAL DEFAULT 4 aa $ bpftool btf dump file t1.o | grep aa [5] VAR 'aa' type_id=4, linkage=static $ bpftool btf dump file output.o | grep aa [5] VAR 't1..aa' type_id=4, linkage=static So yes you are right, this will affect skeleton user if you use static linker with single file. > Since during that step static vars will get their names mangled? > So a good chunk of code that uses skeleton right now should either > 1. don't do the linking step > or > 2. adjust their code to use global vars > or > 3. adjust the usage of skel.h in their corresponding user code > to accommodate mangled static names? > Did it get it right? >