xref: /freebsd/contrib/bc/NEWS.md (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1# News
2
3## 3.2.4
4
5This is a production release that fixes a warning on `gcc` 6 or older, which
6does not have an attribute that is used.
7
8Users do ***NOT*** need to upgrade if they don't use `gcc` 6 or older.
9
10## 3.2.3
11
12This is a production release that fixes a bug in `gen/strgen.sh`. I recently
13changed `gen/strgen.c`, but I did not change `gen/strgen.sh`.
14
15Users that do not use `gen/strgen.sh` do not need to upgrade.
16
17## 3.2.2
18
19This is a production release that fixes a portability bug in `configure.sh`. The
20bug was using the GNU `find` extension `-wholename`.
21
22## 3.2.1
23
24This is a production release that has one fix for `bcl(3)`. It is technically
25not a bug fix since the behavior is undefined, but the `BclNumber`s that
26`bcl_divmod()` returns will be set to `BCL_ERROR_INVALID_NUM` if there is an
27error. Previously, they were not set.
28
29## 3.2.0
30
31This is a production release that has one bug fix and a major addition.
32
33The bug fix was a missing `auto` variable in the bessel `j()` function in the
34math library.
35
36The major addition is a way to build a version of `bc`'s math code as a library.
37This is done with the `-a` option to `configure.sh`. The API for the library can
38be read in `./manuals/bcl.3.md` or `man bcl` once the library is installed with
39`make install`.
40
41This library was requested by developers before I even finished version 1.0, but
42I could not figure out how to do it until now.
43
44If the library has API breaking changes, the major version of `bc` will be
45incremented.
46
47## 3.1.6
48
49This is a production release that fixes a new warning from Clang 12 for FreeBSD
50and also removes some possible undefined behavior found by UBSan that compilers
51did not seem to take advantage of.
52
53Users do ***NOT*** need to upgrade, if they do not want to.
54
55## 3.1.5
56
57This is a production release that fixes the Chinese locales (which caused `bc`
58to crash) and a crash caused by `bc` executing code when it should not have been
59able to.
60
61***ALL USERS SHOULD UPGRADE.***
62
63## 3.1.4
64
65This is a production release that fixes one bug, changes two behaviors, and
66removes one environment variable.
67
68The bug is like the one in the last release except it applies if files are being
69executed. I also made the fix more general.
70
71The behavior that was changed is that `bc` now exits when given `-e`, `-f`,
72`--expression` or `--file`. However, if the last one of those is `-f-` (using
73`stdin` as the file), `bc` does not exit. If `-f-` exists and is not the last of
74the `-e` and `-f` options (and equivalents), `bc` gives a fatal error and exits.
75
76Next, I removed the `BC_EXPR_EXIT` and `DC_EXPR_EXIT` environment variables
77since their use is not needed with the behavior change.
78
79Finally, I made it so `bc` does not print the header, though the `-q` and
80`--quiet` options were kept for compatibility with GNU `bc`.
81
82## 3.1.3
83
84This is a production release that fixes one minor bug: if `bc` was invoked like
85the following, it would error:
86
87```
88echo "if (1 < 3) 1" | bc
89```
90
91Unless users run into this bug, they do not need to upgrade, but it is suggested
92that they do.
93
94## 3.1.2
95
96This is a production release that adds a way to install *all* locales. Users do
97***NOT*** need to upgrade.
98
99For package maintainers wishing to make use of the change, just pass `-l` to
100`configure.sh`.
101
102## 3.1.1
103
104This is a production release that adds two Spanish locales. Users do ***NOT***
105need to upgrade, unless they want those locales.
106
107## 3.1.0
108
109This is a production release that adjusts one behavior, fixes eight bugs, and
110improves manpages for FreeBSD. Because this release fixes bugs, **users and
111package maintainers should update to this version as soon as possible**.
112
113The behavior that was adjusted was how code from the `-e` and `-f` arguments
114(and equivalents) were executed. They used to be executed as one big chunk, but
115in this release, they are now executed line-by-line.
116
117The first bug fix in how output to `stdout` was handled in `SIGINT`. If a
118`SIGINT` came in, the `stdout` buffer was not correctly flushed. In fact, a
119clean-up function was not getting called. This release fixes that bug.
120
121The second bug is in how `dc` handled input from `stdin`. This affected `bc` as
122well since it was a mishandling of the `stdin` buffer.
123
124The third fixed bug was that `bc` and `dc` could `abort()` (in debug mode) when
125receiving a `SIGTERM`. This one was a race condition with pushing and popping
126items onto and out of vectors.
127
128The fourth bug fixed was that `bc` could leave extra items on the stack and
129thus, not properly clean up some memory. (The memory would still get
130`free()`'ed, but it would not be `free()`'ed when it could have been.)
131
132The next two bugs were bugs in `bc`'s parser that caused crashes when executing
133the resulting code.
134
135The last two bugs were crashes in `dc` that resulted from mishandling of
136strings.
137
138The manpage improvement was done by switching from [ronn][20] to [Pandoc][21] to
139generate manpages. Pandoc generates much cleaner manpages and doesn't leave
140blank lines where they shouldn't be.
141
142## 3.0.3
143
144This is a production release that adds one new feature: specific manpages.
145
146Before this release, `bc` and `dc` only used one manpage each that referred to
147various build options. This release changes it so there is one manpage set per
148relevant build type. Each manual only has information about its particular
149build, and `configure.sh` selects the correct set for install.
150
151## 3.0.2
152
153This is a production release that adds `utf8` locale symlinks and removes an
154unused `auto` variable from the `ceil()` function in the [extended math
155library][16].
156
157Users do ***NOT*** need to update unless they want the locales.
158
159## 3.0.1
160
161This is a production release with two small changes. Users do ***NOT*** need to
162upgrade to this release; however, if they haven't upgraded to `3.0.0` yet, it
163may be worthwhile to upgrade to this release.
164
165The first change is fixing a compiler warning on FreeBSD with strict warnings
166on.
167
168The second change is to make the new implementation of `ceil()` in `lib2.bc`
169much more efficient.
170
171## 3.0.0
172
173*Notes for package maintainers:*
174
175*First, the `2.7.0` release series saw a change in the option parsing. This made
176me change one error message and add a few others. The error message that was
177changed removed one format specifier. This means that `printf()` will seqfault
178on old locale files. Unfortunately, `bc` cannot use any locale files except the
179global ones that are already installed, so it will use the previous ones while
180running tests during install. **If `bc` segfaults while running arg tests when
181updating, it is because the global locale files have not been replaced. Make
182sure to either prevent the test suite from running on update or remove the old
183locale files before updating.** (Removing the locale files can be done with
184`make uninstall` or by running the `locale_uninstall.sh` script.) Once this is
185done, `bc` should install without problems.*
186
187*Second, **the option to build without signal support has been removed**. See
188below for the reasons why.*
189
190This is a production release with some small bug fixes, a few improvements,
191three major bug fixes, and a complete redesign of `bc`'s error and signal
192handling. **Users and package maintainers should update to this version as soon
193as possible.**
194
195The first major bug fix was in how `bc` executed files. Previously, a whole file
196was parsed before it was executed, but if a function is defined *after* code,
197especially if the function definition was actually a redefinition, and the code
198before the definition referred to the previous function, this `bc` would replace
199the function before executing any code. The fix was to make sure that all code
200that existed before a function definition was executed.
201
202The second major bug fix was in `bc`'s `lib2.bc`. The `ceil()` function had a
203bug where a `0` in the decimal place after the truncation position, caused it to
204output the wrong numbers if there was any non-zero digit after.
205
206The third major bug is that when passing parameters to functions, if an
207expression included an array (not an array element) as a parameter, it was
208accepted, when it should have been rejected. It is now correctly rejected.
209
210Beyond that, this `bc` got several improvements that both sped it up, improved
211the handling of signals, and improved the error handling.
212
213First, the requirements for `bc` were pushed back to POSIX 2008. `bc` uses one
214function, `strdup()`, which is not in POSIX 2001, and it is in the X/Open System
215Interfaces group 2001. It is, however, in POSIX 2008, and since POSIX 2008 is
216old enough to be supported anywhere that I care, that should be the requirement.
217
218Second, the BcVm global variable was put into `bss`. This actually slightly
219reduces the size of the executable from a massive code shrink, and it will stop
220`bc` from allocating a large set of memory when `bc` starts.
221
222Third, the default Karatsuba length was updated from 64 to 32 after making the
223optimization changes below, since 32 is going to be better than 64 after the
224changes.
225
226Fourth, Spanish translations were added.
227
228Fifth, the interpreter received a speedup to make performance on non-math-heavy
229scripts more competitive with GNU `bc`. While improvements did, in fact, get it
230much closer (see the [benchmarks][19]), it isn't quite there.
231
232There were several things done to speed up the interpreter:
233
234First, several small inefficiencies were removed. These inefficiencies included
235calling the function `bc_vec_pop(v)` twice instead of calling
236`bc_vec_npop(v, 2)`. They also included an extra function call for checking the
237size of the stack and checking the size of the stack more than once on several
238operations.
239
240Second, since the current `bc` function is the one that stores constants and
241strings, the program caches pointers to the current function's vectors of
242constants and strings to prevent needing to grab the current function in order
243to grab a constant or a string.
244
245Third, `bc` tries to reuse `BcNum`'s (the internal representation of
246arbitary-precision numbers). If a `BcNum` has the default capacity of
247`BC_NUM_DEF_SIZE` (32 on 64-bit and 16 on 32-bit) when it is freed, it is added
248to a list of available `BcNum`'s. And then, when a `BcNum` is allocated with a
249capacity of `BC_NUM_DEF_SIZE` and any `BcNum`'s exist on the list of reusable
250ones, one of those ones is grabbed instead.
251
252In order to support these changes, the `BC_NUM_DEF_SIZE` was changed. It used to
253be 16 bytes on all systems, but it was changed to more closely align with the
254minimum allocation size on Linux, which is either 32 bytes (64-bit musl), 24
255bytes (64-bit glibc), 16 bytes (32-bit musl), or 12 bytes (32-bit glibc). Since
256these are the minimum allocation sizes, these are the sizes that would be
257allocated anyway, making it worth it to just use the whole space, so the value
258of `BC_NUM_DEF_SIZE` on 64-bit systems was changed to 32 bytes.
259
260On top of that, at least on 64-bit, `BC_NUM_DEF_SIZE` supports numbers with
261either 72 integer digits or 45 integer digits and 27 fractional digits. This
262should be more than enough for most cases since `bc`'s default `scale` values
263are 0 or 20, meaning that, by default, it has at most 20 fractional digits. And
26445 integer digits are *a lot*; it's enough to calculate the amount of mass in
265the Milky Way galaxy in kilograms. Also, 72 digits is enough to calculate the
266diameter of the universe in Planck lengths.
267
268(For 32-bit, these numbers are either 32 integer digits or 12 integer digits and
26920 fractional digits. These are also quite big, and going much bigger on a
27032-bit system seems a little pointless since 12 digits in just under a trillion
271and 20 fractional digits is still enough for about any use since `10^-20` light
272years is just under a millimeter.)
273
274All of this together means that for ordinary uses, and even uses in scientific
275work, the default number size will be all that is needed, which means that
276nearly all, if not all, numbers will be reused, relieving pressure on the system
277allocator.
278
279I did several experiments to find the changes that had the most impact,
280especially with regard to reusing `BcNum`'s. One was putting `BcNum`'s into
281buckets according to their capacity in powers of 2 up to 512. That performed
282worse than `bc` did in `2.7.2`. Another was putting any `BcNum` on the reuse
283list that had a capacity of `BC_NUM_DEF_SIZE * 2` and reusing them for `BcNum`'s
284that requested `BC_NUM_DEF_SIZE`. This did reduce the amount of time spent, but
285it also spent a lot of time in the system allocator for an unknown reason. (When
286using `strace`, a bunch more `brk` calls showed up.) Just reusing `BcNum`'s that
287had exactly `BC_NUM_DEF_SIZE` capacity spent the smallest amount of time in both
288user and system time. This makes sense, especially with the changes to make
289`BC_NUM_DEF_SIZE` bigger on 64-bit systems, since the vast majority of numbers
290will only ever use numbers with a size less than or equal to `BC_NUM_DEF_SIZE`.
291
292Last of all, `bc`'s signal handling underwent a complete redesign. (This is the
293reason that this version is `3.0.0` and not `2.8.0`.) The change was to move
294from a polling approach to signal handling to an interrupt-based approach.
295
296Previously, every single loop condition had a check for signals. I suspect that
297this could be expensive when in tight loops.
298
299Now, the signal handler just uses `longjmp()` (actually `siglongjmp()`) to start
300an unwinding of the stack until it is stopped or the stack is unwound to
301`main()`, which just returns. If `bc` is currently executing code that cannot be
302safely interrupted (according to POSIX), then signals are "locked." The signal
303handler checks if the lock is taken, and if it is, it just sets the status to
304indicate that a signal arrived. Later, when the signal lock is released, the
305status is checked to see if a signal came in. If so, the stack unwinding starts.
306
307This design eliminates polling in favor of maintaining a stack of `jmp_buf`'s.
308This has its own performance implications, but it gives better interaction. And
309the cost of pushing and popping a `jmp_buf` in a function is paid at most twice.
310Most functions do not pay that price, and most of the rest only pay it once.
311(There are only some 3 functions in `bc` that push and pop a `jmp_buf` twice.)
312
313As a side effect of this change, I had to eliminate the use of `stdio.h` in `bc`
314because `stdio` does not play nice with signals and `longjmp()`. I implemented
315custom I/O buffer code that takes a fraction of the size. This means that static
316builds will be smaller, but non-static builds will be bigger, though they will
317have less linking time.
318
319This change is also good because my history implementation was already bypassing
320`stdio` for good reasons, and unifying the architecture was a win.
321
322Another reason for this change is that my `bc` should *always* behave correctly
323in the presence of signals like `SIGINT`, `SIGTERM`, and `SIGQUIT`. With the
324addition of my own I/O buffering, I needed to also make sure that the buffers
325were correctly flushed even when such signals happened.
326
327For this reason, I **removed the option to build without signal support**.
328
329As a nice side effect of this change, the error handling code could be changed
330to take advantage of the stack unwinding that signals used. This means that
331signals and error handling use the same code paths, which means that the stack
332unwinding is well-tested. (Errors are tested heavily in the test suite.)
333
334It also means that functions do not need to return a status code that
335***every*** caller needs to check. This eliminated over 100 branches that simply
336checked return codes and then passed that return code up the stack if necessary.
337The code bloat savings from this is at least 1700 bytes on `x86_64`, *before*
338taking into account the extra code from removing `stdio.h`.
339
340## 2.7.2
341
342This is a production release with one major bug fix.
343
344The `length()` built-in function can take either a number or an array. If it
345takes an array, it returns the length of the array. Arrays can be passed by
346reference. The bug is that the `length()` function would not properly
347dereference arrays that were references. This is a bug that affects all users.
348
349**ALL USERS SHOULD UPDATE `bc`**.
350
351## 2.7.1
352
353This is a production release with fixes for new locales and fixes for compiler
354warnings on FreeBSD.
355
356## 2.7.0
357
358This is a production release with a bug fix for Linux, new translations, and new
359features.
360
361Bug fixes:
362
363* Option parsing in `BC_ENV_ARGS` was broken on Linux in 2.6.1 because `glibc`'s
364  `getopt_long()` is broken. To get around that, and to support long options on
365  every platform, an adapted version of [`optparse`][17] was added. Now, `bc`
366  does not even use `getopt()`.
367* Parsing `BC_ENV_ARGS` with quotes now works. It isn't the smartest, but it
368  does the job if there are spaces in file names.
369
370The following new languages are supported:
371
372* Dutch
373* Polish
374* Russian
375* Japanes
376* Simplified Chinese
377
378All of these translations were generated using [DeepL][18], so improvements are
379welcome.
380
381There is only one new feature: **`bc` now has a built-in pseudo-random number
382generator** (PRNG).
383
384The PRNG is seeded, making it useful for applications where
385`/dev/urandom` does not work because output needs to be reproducible. However,
386it also uses `/dev/urandom` to seed itself by default, so it will start with a
387good seed by default.
388
389It also outputs 32 bits on 32-bit platforms and 64 bits on 64-bit platforms, far
390better than the 15 bits of C's `rand()` and `bash`'s `$RANDOM`.
391
392In addition, the PRNG can take a bound, and when it gets a bound, it
393automatically adjusts to remove bias. It can also generate numbers of arbitrary
394size. (As of the time of release, the largest pseudo-random number generated by
395this `bc` was generated with a bound of `2^(2^20)`.)
396
397***IMPORTANT: read the [`bc` manual][9] and the [`dc` manual][10] to find out
398exactly what guarantees the PRNG provides. The underlying implementation is not
399guaranteed to stay the same, but the guarantees that it provides are guaranteed
400to stay the same regardless of the implementation.***
401
402On top of that, four functions were added to `bc`'s [extended math library][16]
403to make using the PRNG easier:
404
405* `frand(p)`: Generates a number between `[0,1)` to `p` decimal places.
406* `ifrand(i, p)`: Generates an integer with bound `i` and adds it to `frand(p)`.
407* `srand(x)`: Randomizes the sign of `x`. In other words, it flips the sign of
408  `x` with probability `0.5`.
409* `brand()`: Returns a random boolean value (either `0` or `1`).
410
411## 2.6.1
412
413This is a production release with a bug fix for FreeBSD.
414
415The bug was that when `bc` was built without long options, it would give a fatal
416error on every run. This was caused by a mishandling of `optind`.
417
418## 2.6.0
419
420This release is a production release ***with no bugfixes***. If you do not want
421to upgrade, you don't have to.
422
423No source code changed; the only thing that changed was `lib2.bc`.
424
425This release adds one function to the [extended math library][16]: `p(x, y)`,
426which calculates `x` to the power of `y`, whether or not `y` is an integer. (The
427`^` operator can only accept integer powers.)
428
429This release also includes a couple of small tweaks to the [extended math
430library][16], mostly to fix returning numbers with too high of `scale`.
431
432## 2.5.3
433
434This release is a production release which addresses inconsistencies in the
435Portuguese locales. No `bc` code was changed.
436
437The issues were that the ISO files used different naming, and also that the
438files that should have been symlinks were not. I did not catch that because
439GitHub rendered them the exact same way.
440
441## 2.5.2
442
443This release is a production release.
444
445No code was changed, but the build system was changed to allow `CFLAGS` to be
446given to `CC`, like this:
447
448```
449CC="gcc -O3 -march=native" ./configure.sh
450```
451
452If this happens, the flags are automatically put into `CFLAGS`, and the compiler
453is set appropriately. In the example above this means that `CC` will be "gcc"
454and `CFLAGS` will be "-O3 -march=native".
455
456This behavior was added to conform to GNU autotools practices.
457
458## 2.5.1
459
460This is a production release which addresses portability concerns discovered
461in the `bc` build system. No `bc` code was changed.
462
463* Support for Solaris SPARC and AIX were added.
464* Minor documentations edits were performed.
465* An option for `configure.sh` was added to disable long options if
466  `getopt_long()` is missing.
467
468## 2.5.0
469
470This is a production release with new translations. No code changed.
471
472The translations were contributed by [bugcrazy][15], and they are for
473Portuguese, both Portugal and Brazil locales.
474
475## 2.4.0
476
477This is a production release primarily aimed at improving `dc`.
478
479* A couple of copy and paste errors in the [`dc` manual][10] were fixed.
480* `dc` startup was optimized by making sure it didn't have to set up `bc`-only
481  things.
482* The `bc` `&&` and `||` operators were made available to `dc` through the `M`
483  and `m` commands, respectively.
484* `dc` macros were changed to be tail call-optimized.
485
486The last item, tail call optimization, means that if the last thing in a macro
487is a call to another macro, then the old macro is popped before executing the
488new macro. This change was made to stop `dc` from consuming more and more memory
489as macros are executed in a loop.
490
491The `q` and `Q` commands still respect the "hidden" macros by way of recording
492how many macros were removed by tail call optimization.
493
494## 2.3.2
495
496This is a production release meant to fix warnings in the Gentoo `ebuild` by
497making it possible to disable binary stripping. Other users do *not* need to
498upgrade.
499
500## 2.3.1
501
502This is a production release. It fixes a bug that caused `-1000000000 < -1` to
503return `0`. This only happened with negative numbers and only if the value on
504the left was more negative by a certain amount. That said, this bug *is* a bad
505bug, and needs to be fixed.
506
507**ALL USERS SHOULD UPDATE `bc`**.
508
509## 2.3.0
510
511This is a production release with changes to the build system.
512
513## 2.2.0
514
515This release is a production release. It only has new features and performance
516improvements.
517
5181.	The performance of `sqrt(x)` was improved.
5192.	The new function `root(x, n)` was added to the extended math library to
520	calculate `n`th roots.
5213.	The new function `cbrt(x)` was added to the extended math library to
522	calculate cube roots.
523
524## 2.1.3
525
526This is a non-critical release; it just changes the build system, and in
527non-breaking ways:
528
5291.	Linked locale files were changed to link to their sources with a relative
530	link.
5312.	A bug in `configure.sh` that caused long option parsing to fail under `bash`
532	was fixed.
533
534## 2.1.2
535
536This release is not a critical release.
537
5381.	A few codes were added to history.
5392.	Multiplication was optimized a bit more.
5403.	Addition and subtraction were both optimized a bit more.
541
542## 2.1.1
543
544This release contains a fix for the test suite made for Linux from Scratch: now
545the test suite prints `pass` when a test is passed.
546
547Other than that, there is no change in this release, so distros and other users
548do not need to upgrade.
549
550## 2.1.0
551
552This release is a production release.
553
554The following bugs were fixed:
555
5561.	A `dc` bug that caused stack mishandling was fixed.
5572.	A warning on OpenBSD was fixed.
5583.	Bugs in `ctrl+arrow` operations in history were fixed.
5594.	The ability to paste multiple lines in history was added.
5605.	A `bc` bug, mishandling of array arguments to functions, was fixed.
5616.	A crash caused by freeing the wrong pointer was fixed.
5627.	A `dc` bug where strings, in a rare case, were mishandled in parsing was
563	fixed.
564
565In addition, the following changes were made:
566
5671.	Division was slightly optimized.
5682.	An option was added to the build to disable printing of prompts.
5693.	The special case of empty arguments is now handled. This is to prevent
570	errors in scripts that end up passing empty arguments.
5714.	A harmless bug was fixed. This bug was that, with the pop instructions
572	(mostly) removed (see below), `bc` would leave extra values on its stack for
573	`void` functions and in a few other cases. These extra items would not
574	affect anything put on the stack and would not cause any sort of crash or
575	even buggy behavior, but they would cause `bc` to take more memory than it
576	needed.
577
578On top of the above changes, the following optimizations were added:
579
5801.	The need for pop instructions in `bc` was removed.
5812.	Extra tests on every iteration of the interpreter loop were removed.
5823.	Updating function and code pointers on every iteration of the interpreter
583	loop was changed to only updating them when necessary.
5844.	Extra assignments to pointers were removed.
585
586Altogether, these changes sped up the interpreter by around 2x.
587
588***NOTE***: This is the last release with new features because this `bc` is now
589considered complete. From now on, only bug fixes and new translations will be
590added to this `bc`.
591
592## 2.0.3
593
594This is a production, bug-fix release.
595
596Two bugs were fixed in this release:
597
5981.	A rare and subtle signal handling bug was fixed.
5992.	A misbehavior on `0` to a negative power was fixed.
600
601The last bug bears some mentioning.
602
603When I originally wrote power, I did not thoroughly check its error cases;
604instead, I had it check if the first number was `0` and then if so, just return
605`0`. However, `0` to a negative power means that `1` will be divided by `0`,
606which is an error.
607
608I caught this, but only after I stopped being cocky. You see, sometime later, I
609had noticed that GNU `bc` returned an error, correctly, but I thought it was
610wrong simply because that's not what my `bc` did. I saw it again later and had a
611double take. I checked for real, finally, and found out that my `bc` was wrong
612all along.
613
614That was bad on me. But the bug was easy to fix, so it is fixed now.
615
616There are two other things in this release:
617
6181.	Subtraction was optimized by [Stefan Eßer][14].
6192.	Division was also optimized, also by Stefan Eßer.
620
621## 2.0.2
622
623This release contains a fix for a possible overflow in the signal handling. I
624would be surprised if any users ran into it because it would only happen after 2
625billion (`2^31-1`) `SIGINT`'s, but I saw it and had to fix it.
626
627## 2.0.1
628
629This release contains very few things that will apply to any users.
630
6311.	A slight bug in `dc`'s interactive mode was fixed.
6322.	A bug in the test suite that was only triggered on NetBSD was fixed.
6333.	**The `-P`/`--no-prompt` option** was added for users that do not want a
634	prompt.
6354.	A `make check` target was added as an alias for `make test`.
6365.	`dc` got its own read prompt: `?> `.
637
638## 2.0.0
639
640This release is a production release.
641
642This release is also a little different from previous releases. From here on
643out, I do not plan on adding any more features to this `bc`; I believe that it
644is complete. However, there may be bug fix releases in the future, if I or any
645others manage to find bugs.
646
647This release has only a few new features:
648
6491.	`atan2(y, x)` was added to the extended math library as both `a2(y, x)` and
650	`atan2(y, x)`.
6512.	Locales were fixed.
6523.	A **POSIX shell-compatible script was added as an alternative to compiling
653	`gen/strgen.c`** on a host machine. More details about making the choice
654	between the two can be found by running `./configure.sh --help` or reading
655	the [build manual][13].
6564.	Multiplication was optimized by using **diagonal multiplication**, rather
657	than straight brute force.
6585.	The `locale_install.sh` script was fixed.
6596.	`dc` was given the ability to **use the environment variable
660	`DC_ENV_ARGS`**.
6617.	`dc` was also given the ability to **use the `-i` or `--interactive`**
662	options.
6638.	Printing the prompt was fixed so that it did not print when it shouldn't.
6649.	Signal handling was fixed.
66510.	**Handling of `SIGTERM` and `SIGQUIT`** was fixed.
66611.	The **built-in functions `maxibase()`, `maxobase()`, and `maxscale()`** (the
667	commands `T`, `U`, `V` in `dc`, respectively) were added to allow scripts to
668	query for the max allowable values of those globals.
66912.	Some incompatibilities with POSIX were fixed.
670
671In addition, this release is `2.0.0` for a big reason: the internal format for
672numbers changed. They used to be a `char` array. Now, they are an array of
673larger integers, packing more decimal digits into each integer. This has
674delivered ***HUGE*** performance improvements, especially for multiplication,
675division, and power.
676
677This `bc` should now be the fastest `bc` available, but I may be wrong.
678
679## 1.2.8
680
681This release contains a fix for a harmless bug (it is harmless in that it still
682works, but it just copies extra data) in the [`locale_install.sh`][12] script.
683
684## 1.2.7
685
686This version contains fixes for the build on Arch Linux.
687
688## 1.2.6
689
690This release removes the use of `local` in shell scripts because it's not POSIX
691shell-compatible, and also updates a man page that should have been updated a
692long time ago but was missed.
693
694## 1.2.5
695
696This release contains some missing locale `*.msg` files.
697
698## 1.2.4
699
700This release contains a few bug fixes and new French translations.
701
702## 1.2.3
703
704This release contains a fix for a bug: use of uninitialized data. Such data was
705only used when outputting an error message, but I am striving for perfection. As
706Michelangelo said, "Trifles make perfection, and perfection is no trifle."
707
708## 1.2.2
709
710This release contains fixes for OpenBSD.
711
712## 1.2.1
713
714This release contains bug fixes for some rare bugs.
715
716## 1.2.0
717
718This is a production release.
719
720There have been several changes since `1.1.0`:
721
7221.	The build system had some changes.
7232.	Locale support has been added. (Patches welcome for translations.)
7243.	**The ability to turn `ibase`, `obase`, and `scale` into stacks** was added
725	with the `-g` command-line option. (See the [`bc` manual][9] for more
726	details.)
7274.	Support for compiling on Mac OSX out of the box was added.
7285.	The extended math library got `t(x)`, `ceil(x)`, and some aliases.
7296.	The extended math library also got `r2d(x)` (for converting from radians to
730	degrees) and `d2r(x)` (for converting from degrees to radians). This is to
731	allow using degrees with the standard library.
7327.	Both calculators now accept numbers in **scientific notation**. See the
733	[`bc` manual][9] and the [`dc` manual][10] for details.
7348.	Both calculators can **output in either scientific or engineering
735	notation**. See the [`bc` manual][9] and the [`dc` manual][10] for details.
7369.	Some inefficiencies were removed.
73710.	Some bugs were fixed.
73811.	Some bugs in the extended library were fixed.
73912.	Some defects from [Coverity Scan][11] were fixed.
740
741## 1.1.4
742
743This release contains a fix to the build system that allows it to build on older
744versions of `glibc`.
745
746## 1.1.3
747
748This release contains a fix for a bug in the test suite where `bc` tests and
749`dc` tests could not be run in parallel.
750
751## 1.1.2
752
753This release has a fix for a history bug; the down arrow did not work.
754
755## 1.1.1
756
757This release fixes a bug in the `1.1.0` build system. The source is exactly the
758same.
759
760The bug that was fixed was a failure to install if no `EXECSUFFIX` was used.
761
762## 1.1.0
763
764This is a production release. However, many new features were added since `1.0`.
765
7661.	**The build system has been changed** to use a custom, POSIX
767	shell-compatible configure script ([`configure.sh`][6]) to generate a POSIX
768	make-compatible `Makefile`, which means that `bc` and `dc` now build out of
769	the box on any POSIX-compatible system.
7702.	Out-of-memory and output errors now cause the `bc` to report the error,
771	clean up, and die, rather than just reporting and trying to continue.
7723.	**Strings and constants are now garbage collected** when possible.
7734.	Signal handling and checking has been made more simple and more thorough.
7745.	`BcGlobals` was refactored into `BcVm` and `BcVm` was made global. Some
775	procedure names were changed to reflect its difference to everything else.
7766.	Addition got a speed improvement.
7777.	Some common code for addition and multiplication was refactored into its own
778	procedure.
7798.	A bug was removed where `dc` could have been selected, but the internal
780	`#define` that returned `true` for a query about `dc` would not have
781	returned `true`.
7829.	Useless calls to `bc_num_zero()` were removed.
78310.	**History support was added.** The history support is based off of a
784	[UTF-8 aware fork][7] of [`linenoise`][8], which has been customized with
785	`bc`'s own data structures and signal handling.
78611.	Generating C source from the math library now removes tabs from the library,
787	shrinking the size of the executable.
78812.	The math library was shrunk.
78913.	Error handling and reporting was improved.
79014.	Reallocations were reduced by giving access to the request size for each
791	operation.
79215.	**`abs()` (`b` command for `dc`) was added as a builtin.**
79316.	Both calculators were tested on FreeBSD.
79417.	Many obscure parse bugs were fixed.
79518.	Markdown and man page manuals were added, and the man pages are installed by
796	`make install`.
79719.	Executable size was reduced, though the added features probably made the
798	executable end up bigger.
79920.	**GNU-style array references were added as a supported feature.**
80021.	Allocations were reduced.
80122.	**New operators were added**: `$` (`$` for `dc`), `@` (`@` for `dc`), `@=`,
802	`<<` (`H` for `dc`), `<<=`, `>>` (`h` for `dc`), and `>>=`. See the
803	[`bc` manual][9] and the [`dc` manual][10] for more details.
80423.	**An extended math library was added.** This library contains code that
805	makes it so I can replace my desktop calculator with this `bc`. See the
806	[`bc` manual][3] for more details.
80724.	Support for all capital letters as numbers was added.
80825.	**Support for GNU-style void functions was added.**
80926.	A bug fix for improper handling of function parameters was added.
81027.	Precedence for the or (`||`) operator was changed to match GNU `bc`.
81128.	`dc` was given an explicit negation command.
81229.	`dc` was changed to be able to handle strings in arrays.
813
814## 1.1 Release Candidate 3
815
816This release is the eighth release candidate for 1.1, though it is the third
817release candidate meant as a general release candidate. The new code has not
818been tested as thoroughly as it should for release.
819
820## 1.1 Release Candidate 2
821
822This release is the seventh release candidate for 1.1, though it is the second
823release candidate meant as a general release candidate. The new code has not
824been tested as thoroughly as it should for release.
825
826## 1.1 FreeBSD Beta 5
827
828This release is the sixth release candidate for 1.1, though it is the fifth
829release candidate meant specifically to test if `bc` works on FreeBSD. The new
830code has not been tested as thoroughly as it should for release.
831
832## 1.1 FreeBSD Beta 4
833
834This release is the fifth release candidate for 1.1, though it is the fourth
835release candidate meant specifically to test if `bc` works on FreeBSD. The new
836code has not been tested as thoroughly as it should for release.
837
838## 1.1 FreeBSD Beta 3
839
840This release is the fourth release candidate for 1.1, though it is the third
841release candidate meant specifically to test if `bc` works on FreeBSD. The new
842code has not been tested as thoroughly as it should for release.
843
844## 1.1 FreeBSD Beta 2
845
846This release is the third release candidate for 1.1, though it is the second
847release candidate meant specifically to test if `bc` works on FreeBSD. The new
848code has not been tested as thoroughly as it should for release.
849
850## 1.1 FreeBSD Beta 1
851
852This release is the second release candidate for 1.1, though it is meant
853specifically to test if `bc` works on FreeBSD. The new code has not been tested as
854thoroughly as it should for release.
855
856## 1.1 Release Candidate 1
857
858This is the first release candidate for 1.1. The new code has not been tested as
859thoroughly as it should for release.
860
861## 1.0
862
863This is the first non-beta release. `bc` is ready for production use.
864
865As such, a lot has changed since 0.5.
866
8671.	`dc` has been added. It has been tested even more thoroughly than `bc` was
868	for `0.5`. It does not have the `!` command, and for security reasons, it
869	never will, so it is complete.
8702.	`bc` has been more thoroughly tested. An entire section of the test suite
871	(for both programs) has been added to test for errors.
8723.	A prompt (`>>> `) has been added for interactive mode, making it easier to
873	see inputs and outputs.
8744.	Interrupt handling has been improved, including elimination of race
875	conditions (as much as possible).
8765.	MinGW and [Windows Subsystem for Linux][1] support has been added (see
877	[xstatic][2] for binaries).
8786.	Memory leaks and errors have been eliminated (as far as ASan and Valgrind
879	can tell).
8807.	Crashes have been eliminated (as far as [afl][3] can tell).
8818.	Karatsuba multiplication was added (and thoroughly) tested, speeding up
882	multiplication and power by orders of magnitude.
8839.	Performance was further enhanced by using a "divmod" function to reduce
884	redundant divisions and by removing superfluous `memset()` calls.
88510.	To switch between Karatsuba and `O(n^2)` multiplication, the config variable
886	`BC_NUM_KARATSUBA_LEN` was added. It is set to a sane default, but the
887	optimal number can be found with [`karatsuba.py`][4] (requires Python 3)
888	and then configured through `make`.
88911.	The random math test generator script was changed to Python 3 and improved.
890	`bc` and `dc` have together been run through 30+ million random tests.
89112.	All known math bugs have been fixed, including out of control memory
892	allocations in `sine` and `cosine` (that was actually a parse bug), certain
893	cases of infinite loop on square root, and slight inaccuracies (as much as
894	possible; see the [README][5]) in transcendental functions.
89513.	Parsing has been fixed as much as possible.
89614.	Test coverage was improved to 94.8%. The only paths not covered are ones
897	that happen when `malloc()` or `realloc()` fails.
89815.	An extension to get the length of an array was added.
89916.	The boolean not (`!`) had its precedence change to match negation.
90017.	Data input was hardened.
90118.	`bc` was made fully compliant with POSIX when the `-s` flag is used or
902	`POSIXLY_CORRECT` is defined.
90319.	Error handling was improved.
90420.	`bc` now checks that files it is given are not directories.
905
906## 1.0 Release Candidate 7
907
908This is the seventh release candidate for 1.0. It fixes a few bugs in 1.0
909Release Candidate 6.
910
911## 1.0 Release Candidate 6
912
913This is the sixth release candidate for 1.0. It fixes a few bugs in 1.0 Release
914Candidate 5.
915
916## 1.0 Release Candidate 5
917
918This is the fifth release candidate for 1.0. It fixes a few bugs in 1.0 Release
919Candidate 4.
920
921## 1.0 Release Candidate 4
922
923This is the fourth release candidate for 1.0. It fixes a few bugs in 1.0 Release
924Candidate 3.
925
926## 1.0 Release Candidate 3
927
928This is the third release candidate for 1.0. It fixes a few bugs in 1.0 Release
929Candidate 2.
930
931## 1.0 Release Candidate 2
932
933This is the second release candidate for 1.0. It fixes a few bugs in 1.0 Release
934Candidate 1.
935
936## 1.0 Release Candidate 1
937
938This is the first Release Candidate for 1.0. `bc` is complete, with `dc`, but it
939is not tested.
940
941## 0.5
942
943This beta release completes more features, but it is still not complete nor
944tested as thoroughly as necessary.
945
946## 0.4.1
947
948This beta release fixes a few bugs in 0.4.
949
950## 0.4
951
952This is a beta release. It does not have the complete set of features, and it is
953not thoroughly tested.
954
955[1]: https://docs.microsoft.com/en-us/windows/wsl/install-win10
956[2]: https://pkg.musl.cc/bc/
957[3]: http://lcamtuf.coredump.cx/afl/
958[4]: ./karatsuba.py
959[5]: ./README.md
960[6]: ./configure.sh
961[7]: https://github.com/rain-1/linenoise-mob
962[8]: https://github.com/antirez/linenoise
963[9]: ./manuals/bc/A.1.md
964[10]: ./manuals/dc/A.1.md
965[11]: https://scan.coverity.com/projects/gavinhoward-bc
966[12]: ./locale_install.sh
967[13]: ./manuals/build.md
968[14]: https://github.com/stesser
969[15]: https://github.com/bugcrazy
970[16]: ./manuals/bc/A.1.md#extended-library
971[17]: https://github.com/skeeto/optparse
972[18]: https://www.deepl.com/translator
973[19]: ./manuals/benchmarks.md
974[20]: https://github.com/apjanke/ronn-ng
975[21]: https://pandoc.org/
976