There is no "C's convenient inline assembly": that is a vendor extension, if available, and its convenience could vary considerably. The manipulation of memory

There is no "C's convenient inline assembly": that is a vendor extension, if available, and its convenience could vary considerably. The manipulation of memory by C programs is close semantically to the manipulation of memory by assembly programs. Memory accessed through pointers is similarly "external" to both assembly language and C programs. The evaluation of C program code is not close to assembly language. C programs cannot reflect on themselves portably; features like parameter passing, returning, and allocating local storage during procedure activation, are not in the programming model. C loses access to detailed machine state. Errors that machine language can catch, like overflows, division by zero and whatnot, are "undefined behavior". An assembly language program can easily add two integers together and then two more integers which include the carry out from the previous addition. Not so in C. Assembly language instruction set designs (with some exceptions) tend to bend over backwards to preserve the functioning of existing binary programs, by maintaining the illusion that instructions are executed in sequence as if there were no pipelining or speculative execution, or register renaming, etc. Meanwhile, C compiler vendors bend over backwards to prove that code you wrote 17 years ago was wrong and make it fail. C is full of unspecified evaluation orders and various kinds of undefined behavior in just the basic evaluation model of its syntactic, built-in constructs; and then some more in the use of libraries. In assembly language, you would never have doubt about the order of evaluation of arguments for a procedure. Even when it comes to memory, where C and asasembly language agree in many points, there are some subtle ways C can screw you. In assembly language, you would never wonder whether copying a structure from one memory location to another included the alignment padding bits. In C you also don't have to wonder, if you use memcpy. Oh, but if you use memset to clear some memory which you don't touch afterward and which goes out of scope, the compiler can optimize that away, oops!