From: antispam@fricas.org   
      
   Philipp Klaus Krause  wrote:   
   > Am 24.11.25 um 15:21 schrieb bart:   
   >>>> I had been responding to the claim that those smaller types save   
   >>>> memory, compared to using sizes 8/16/32 bits which are commonly   
   >>>> available and have better hardware support.   
   >>>   
   >>> I don't recall any such claim.  Do you have a citation (other than   
   >>> the FPGA-specific wording in N2709)?   
   >>   
   >> This is where it came up in this thread:   
   >>   
   >> On 23/11/2025 11:46, Philipp Klaus Krause wrote:   
   >>  > Am 22.10.25 um 14:45 schrieb Thiago Adams:   
   >>  >>   
   >>  >>   
   >>  >> Is anyone using or planning to use this new C23 feature?   
   >>  >> What could be the motivation?   
   >>  >>   
   >>  >>   
   >>  >   
   >>  > Saving memory by using the smallest multiple-of-8 N that will do. Also   
   >>  > being able to use bit-fields wider than int.   
   >>  >   
   >>  > Saving memory for two reasons:   
   >>  >   
   >>  > * On small embedded systems where there is very little memory   
   >>  > * For code that needs to be very fast on big systems to make data   
   >>  > structures fit into cache   
   >>  >   
   >>   
   >> Although this doesn't go as far as using odd bit-sizes: it would mean   
   >> using sizes like 24, 40, 48, and 56 bits instead of 32 or 64 bits.   
   >>   
   >> The savings would be sparse.   
   >>   
   >>   
   >   
   > "On small embedded systems" - those tend to be 8-bit systems, so   
   > compilers targeting them would only round up to multiple of 8, i.e. a   
   > BitInt(40) is exactly 5 bytes. Also "bit-fields wider than int" - for   
   > bit-fields it can indeed make sense to have a width that is not a   
   > multiple of 8, if the remaining bits of the last byte can be used for   
   > other purposes.   
      
   I think it is better to say "8-bit systems".  People here wrote   
   that RPi Pico with its 256 kB RAM and megabytes of flash is small.   
   I have CH32V003, 32-bit MCU which has 2 KB RAM and 16 kB flash,   
   I would call it small.  MSP430 is 16-bit, and was available with   
   some tiny RAM and 2 kB flash, I would say that most embedded   
   systems (counting projects, not number chips/subsystems that were   
   manufactured) is bigger.  Clearly 8-bit MCU-s are used in some   
   high-volume projects, but now one can get relatively small   
   32-bit MCU-s and various statistics indicate that 32-bit   
   MCU-s get more use than 8-bit ones.  So, claim that "small   
   embedded systems tend to be 8-bit systems" is debatable.   
      
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