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C is actually "high-level" in most aspects and we tend to forget that because of newer languages with lots of bells and whistles. C gives you a lot over assembl

C is actually "high-level" in most aspects and we tend to forget that because of newer languages with lots of bells and whistles. C gives you a lot over assembly: functions with (mostly) no need to worry about calling conventions, automatic variables instead of dealing with registers and stack frame offsets, expression-oriented syntax that facilitates nesting of many operations within a single statement, structured programming support instead of scattered jumps and a rudimentary type system around values, pointers, arrays and structs. Nothing fancy, but it means that the language can be compiled in a straightforward manner without any runtime support and a programmer can easily have a complete mental model of it.

pjmlp 10y ago
Compared with languages like Ada, Modula-2, Turbo Pascal, Mesa/Cedar, Algol, PL/I, C is what we used to call a middle level language in those days. And Algol, PL/I and their respective variants are around 10 years older than C.
adrianratnapala 10y ago
Indeed. I don't want to give the impression that C is just assembly. It gives all the advantages you name, and they are very important. But I still say that C is a way of talking about same things you want to talk about in assembly, albeit while automating some tedious but important things like register allocation. You are still commanding the computer at a low level: still telling it which byte to put on which IO port or memory location. Of course you can build higher level abstractions on this -- but only to a point. C compilers go wrong when they imagine a C program lives in such a higher level of abstraction -- whereas the other languages thrive on defining such abstract machines.
- colanderman 10y ago
  But you can't actually directly address I/O ports in C, and directly addressing memory (via pointer arithmetic which oversteps the bounds of an object, or which puns the type of an object) invokes undefined behavior. Both those things depend on details of the underlying architecture, ABI, and operating system, and are abstracted away in C.

pjmlp 10y ago

Compared with languages like Ada, Modula-2, Turbo Pascal, Mesa/Cedar, Algol, PL/I, C is what we used to call a middle level language in those days. And Algol, PL/I and their respective variants are around 10 years older than C.

adrianratnapala 10y ago

Indeed. I don't want to give the impression that C is just assembly. It gives all the advantages you name, and they are very important. But I still say that C is a way of talking about same things you want to talk about in assembly, albeit while automating some tedious but important things like register allocation. You are still commanding the computer at a low level: still telling it which byte to put on which IO port or memory location. Of course you can build higher level abstractions on this -- but only to a point. C compilers go wrong when they imagine a C program lives in such a higher level of abstraction -- whereas the other languages thrive on defining such abstract machines.

colanderman 10y ago
But you can't actually directly address I/O ports in C, and directly addressing memory (via pointer arithmetic which oversteps the bounds of an object, or which puns the type of an object) invokes undefined behavior. Both those things depend on details of the underlying architecture, ABI, and operating system, and are abstracted away in C.