[h2root] Adapt to GCC 8 passing convention for string length

[guitargeek]

According to the gfortran argument passing conventions, for any Fortran procedure, the compiler will automatically define a C prototype. This is what we use in h2root.

Note that for procedures like HROPEN that takes string arguments, the signature of the C prototype will have extra arguments for the string lengths, which we also have to include in our forward declaration and usage. However, the type of these was changed with GCC 8 to size_t, so we have to also account for that as recommended in [1]. Otherwise, we get undefined behavor, which causes the h2root test to fail on ARM64 with GCC 14.

[1] https://gcc.gnu.org/onlinedocs/gfortran/Argument-passing-conventions.html

See also this PR that tests this commit on Alma 10 ARM, with GCC 14:

• [ci] Use AlmaLinux 10 for ARM build #20501

[pcanal]

Thanks.

[ferdymercury]

Thanks a lot for this!
Could you remove the -O0 flag in
set_target_properties(minicern PROPERTIES COMPILE_FLAGS "-O0 -w")

to see if it's now good or if there are still issues somewhere?

As well as locally add:

set_target_properties(minicern PROPERTIES COMPILE_FLAGS "-fsanitize=undefined -fsanitize=address")
target_link_options(minicern BEFORE PUBLIC -fsanitize=undefined PUBLIC -fsanitize=address)

[guitargeek]

Ok! I'll try in a separate PR after this one is merged, so we can see what happens

[ferdymercury]

Just tried your changes locally on Ubuntu 22, with sanitizer enabled, and I still get:

/opt/root_src/misc/minicern/src/zebra.f:6746:72: runtime error: load of address 0x555556df372c with insufficient space for an object of type 'integer(kind=4)'
0x555556df372c: note: pointer points here
  24 02 00 00 18 2f 0f 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
              ^ 
/opt/root_src/misc/minicern/src/zebra.f:6747:72: runtime error: load of address 0x555556df372c with insufficient space for an object of type 'integer(kind=4)'
0x555556df372c: note: pointer points here
  24 02 00 00 18 2f 0f 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
              ^ 
/opt/root_src/misc/minicern/src/zebra.f:6753:72: runtime error: store to address 0x555556df372c with insufficient space for an object of type 'integer(kind=4)'
0x555556df372c: note: pointer points here
  24 02 00 00 18 2f 0f 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
              ^ 
 Converting directory //example

but I guess that's an unrelated issue.

[ferdymercury]

Maybe "mac14-fortran=OFF" line could be removed now from the CI-config-file.