Support for more CPU types. LLVM is limited to the mainstream architectures.
> https://en.wikipedia.org/wiki/GNU_Compiler_Collection#Archit...
And the number of architectures by LLVM:
> https://en.wikipedia.org/wiki/LLVM#Back_ends
GCC supports vastly more targets.
> The C standard uses the term byte to mean the minimum addressable unit in the implementation, which is char, which means a byte on these targets is 16 bits. This is in conflict with the widespread use of byte to mean 8 bits exactly. This is an unfortunate disagreement between C terminology and widespread industry terminology that TI can't do anything about.
In the past, architectures differed wildly in number of bits per byte, e.g 36 for the machine where the Pascal language was created.
Today, the industry mostly standardized on 8 bits per byte, but see e.g the PIC architecture for an example relevant today with a different choice: 8 bit bytes for data, but 10 bit bytes for instructions.
I think that's an anachronistic/incorrect usage. A lot of machines (including several with 36-bit words that you mentioned) supported larger basic addressable units of memory, but didn't call these larger units "bytes", and distinguished between "bytes" and "words". In fact, one of the elements of the early RISC philosophy was that CPU support for byte accesses (as opposed to word accesses) was extraneous, based on statistics gathered from real programs. Early MIPS/Alpha/etc. machines did not support byte addressing, but the people using them still called 8 bits a byte.