But without pointer indirection and dynamic memory allocation, why even use C? The big idea of C is pointers. Aren't there languages designed for mission critical and embedded environments (Ada for instance) ?
This is a much larger discussion, akin to most religious wars in software ;-). There is a huge argument for what you're saying, but there's other forces at play. One aspect that plays into it is that C is a really nice layer on top of assembly, and there are a lot of extremely talented embedded C software engineers, (I'm assuming) moreso than the number of available Ada engineers. Also, keep in mind this is a pretty conservative domain. What has worked in the past is trusted much more than what might work better. Up until a decade or so, there was no operating system to speak of and most development used hardware controllers.
Also, C is not the only horse in town. In fact, I hear that Ada is actually pretty popular in space-flight. Other missions have successfully leveraged FORTH even. Using a Lisp read-eval print loop from many millions of miles away once saved the Voyager mission.
In my experience, I have never come across Ada in the spaceflight domain.
Among the big players in spacecraft flight software, there seems to be a divergent east-coast/west-coast preference for C and C++, respectively. In my estimation, this is the reason: there is a wide variety of target hardware and OSes and the need for FSW to be reused across all of them (embedded linux, VxWorks, QNX on PowerPC, SPARC, intel architectures). In terms of development environments and compiler toolchains, only ISO C (and to a slightly lesser degree C++) is supported by all of them.
Edit: Various instruments on spacecraft may be programmed in Forth or other nifty languages, for example, and there's a growing effort to make some of the more "interesting" challenges in spaceflight (autonomy, fault management, guidance-and-control, etc..) to be coded in custom domain-specific languages or other scripting languages like Lua.
What do pointers have to do with memory allocation? Pointers don't discriminate against the otherwise allocated.
That said, this system still uses a dynamic memory system - its somewhat non-optional when you use an operating system which has to maintain memory for stacks and its own resources.
These guidelines just forbid you to use the memory allocation routines after the task initialization phase to make memory allocation and usage completely predictable.
I brought up pointer indirections as a way of illustrating how stringent some of these rules are and what sorts of forces are at play. Sorry for muddying matters.
The point is that you can still do all of that stuff even on staticly allocated memory.
The other limitation in a lot of these systems is the underlying virtual memory system and some times there isn't one. Memory fragmentation issues are a huge problem when you have a couple kB to a few MB of physical RAM and a limited VM subsystem.
