Shifting 32-bit off_t with 32 bits

[azisso]

Hey,
I get a warning for this line:
https://github.com/mirror/dmidecode/blob/master/dmidecode.c#L4835-L4836
When compiling on a x86 machine:

myfile.cpp: In function 'std::string smbios3_decode(u8*, const char*, u32)':
myfile.cpp:474:39: warning: left shift count >= width of type [-Wshift-count-overflow]
return dmi_table(((off_t)offset.h << 32) | offset.l,
^

That seems like it could be a problem. What do you guys think?