messed up startup

  /* we'll make the assumption in the following code that these statics
   * will be allocated into the same bank.

When I first saw the this comment in the MCC18 C startup code some time ago, it sent a chill down my spine. But promptly I recovered, after all, this is one of the most widely used MCU on the planet and this is the preferred development environment. If they did it this way, they would have good reasons.

Then I wasted a whole afternoon tracking a problem in initialization, only to discover that the assumption had been silently broken by the linker and the code ceased to properly work, wreaking havoc in initialization of the static data.
It is beyond my understanding how could you, while professionally doing your job, base a core component (the startup code) on such assumption without either being sure that the assumption is always correct or there is an automatic detection that reports when the assumption no longer holds true.
Objectively it would have been fairer to provide a less efficient version safely and always working leaving to the eager programmer the task of crafting a high performance version if needed, rather than vice-versa.
Valentino, in comments to a previous post, asked me if I have data about difference in pricing among PIC and other MCUs. Well, not handy, but the difference is really small (my guess is 0.5€ to 1.5€) and it doesn’t really make sense to undergo all these troubles unless your volumes are filthy high.

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