Too many digits (Mac M1)

simonjwright commented 1 year ago

$ ./hac test/digitz.adb 
test/digitz.adb: 56:32-32: number is too large: total actual exponent is  16 > Max = 15
test/digitz.adb: 57:4-12: duplicate identifier: PUT_LINE
Errors found, build failed.

Two, maybe 3, problems here:

I don’t think it’s an exponent problem, looks more like a significant digits problem
Should it be an error, anyway?
Failed to recover, see the duplicate identifier message at line 57

The reason that 16 digits is too many is that, on aarch64-apple-darwin (and maybe other aarch64 systems?), Long_Long_Float is the same as Long_Float; we have

   type Long_Float is digits 15
     range -16#0.FFFF_FFFF_FFFF_F8#E256 .. 16#0.FFFF_FFFF_FFFF_F8#E256;
   for Long_Float'Size use 64;

   type Long_Long_Float is digits 15
     range -16#0.FFFF_FFFF_FFFF_F8#E256 .. 16#0.FFFF_FFFF_FFFF_F8#E256;
   for Long_Long_Float'Size use 64;

vs on x86_64-apple-darwin we get

   type Long_Float is digits 15
     range -16#0.FFFF_FFFF_FFFF_F8#E256 .. 16#0.FFFF_FFFF_FFFF_F8#E256;
   for Long_Float'Size use 64;

   type Long_Long_Float is digits 18
     range -16#0.FFFF_FFFF_FFFF_FFFF#E4096 .. 16#0.FFFF_FFFF_FFFF_FFFF#E4096;
   for Long_Long_Float'Size use 128;

The all_silent_tests.adb test runs successfully.

This is with commit 5841f9d.

zertovitch commented 1 year ago

Thanks for the report. Actually you discovered a bunch of issues - ouch! And by looking at the code there is an obvious supplemental one: there is an overflow when the integer scanned before the dot is too large.

zertovitch commented 1 year ago

Commit https://github.com/zertovitch/hac/commit/ae9cc77bc19347fe07fa4d1bbe6d71d6f74210ca should solve the issue. To summarize:

Same error message was used for two completely different kinds of errors.
The limitation is actually related to the integer part of a number literal (float or not!). It is now detected at the right place and with the right maximum number of digits (decimal representation of 2**63, minus 1 digit). I have let as "to do" the use of multi-precision integers for the job...
The error recovery is fixed.

simonjwright commented 1 year ago

Looking good, thanks!

zertovitch commented 1 year ago

So the test works now on your macs and we can close the issue ? (It seems obvious that it should work, but I am a bit superstitious sometimes ;-) ).

simonjwright commented 1 year ago

digitz.adb works. all_silent_tests.adb works.

Closing ...

zertovitch / hac

Too many digits (Mac M1) #13