Add entries to FAQ + minor fixes to thanks file

The following entries were added:

0. Makefile rules.
1. 32-bit entries not working in 64-bit systems.
2. Some entries not working in macOS either uncompilable or
non-functional.
3. Entries that cannot be compiled with clang.

For (3) this especially is problematic for macOS as even /usr/bin/gcc is
clang (as has been noted many times before this but not in the FAQ).

At least one typo fix was also made and at least one entry that already
existed was updated a bit.

The fixes to the thanks file are related to the FAQ entries added.

faq.md

@@ -31,8 +31,55 @@
 By tradition, we do not say.
 
 ## Q: How many judging rounds do you have?
+
 Are you trying to trick us? We will not say that either.
 
+## Q: What are the general Makefile rules used in order to clean and build entries for use?
+
+In general the best way to compile everything in an entry directory is to run:
+
+```sh
+make clobber all
+```
+
+If you wish to compile every entry for every year you should go to the top level
+directory and run the same command as above, `make clobber all`.
+
+The `all` rule will build everything necessary except for the alternate
+versions. Every Makefile has an `alt` rule but it will only do something if an
+alternate version exists. To build all the entries along with any alternate code
+you can do from the top level directory:
+
+```
+make clobber everything
+```
+
+If you wish to only build alternate code you can do:
+
+```sh
+make clobber alt
+```
+
+If you wish to not remove the entry binaries and only compile the additional alt
+versions:
+
+```sh
+make alt
+```
+
+
+The following Makefile rules should be in all Makefiles:
+
+- all: build the entry programs (main program and any supplementary program)
+- alt: build alternate code
+- clobber: clean up object files and all binary files (except for those that are
+not compiled)
+- clean: a simpler version of `clobber` that only removes object files. `make
+clobber` depends on `clean` so running `make clobber` will invoke `make clean`.
+- everything: equivalent to `make all alt`.
+
+Are there any other rules? You tell us!
+
 ## Q: How come some entries have code that is incongruent with what the author(s) wrote about the entry?
 
 It is very likely in this case that the code was fixed to work for modern
@@ -41,6 +88,7 @@ some entries you should look at the original code as in `winner.orig.c` or
 `prog.orig.c`. Sometimes the original is in an alt version like `winner.alt.c`
 or `prog.alt.c`.
 
+
 ## Q: I cannot get entry XYZZY from year 19xx to compile!
 
 Some winners, particularly winners from long ago, no longer compile on more
@@ -65,7 +113,7 @@ The microseconds defaults to 10000.
 Thank you Cody!
 
 See also [Yusuke Endoh](/winners.html#Yusuke_Endoh)'s entry
-[2015/endoh3](/2015/endoh3/README.md) entry which lets one compile it and run
+[2015/endoh3](/2015/endoh3/README.md) which lets one compile it and run
 it. Another entry that you can enjoy it under is [Christopher
 Mill](/winners.html#Christopher_Mills)'s entry
 [2018/mills](/2018/mills/README.md) which is a PDP-7 emulator as well as a
@@ -79,6 +127,43 @@ time).
 In some cases we replaced the original code with code that works for modern
 systems but one can view the original code in the `.orig.c` files (sometimes the
 original code is also in the directory as a `winner.alt.c` or `prog.alt.c`).
+Some entries should not have modern system versions replaced. See below.
+
+## Q: I can't get some entries to work in 64-bit systems that don't support 32-bit!
+
+Unfortunately some older entries are non-portable and require 32-bit support of
+32-bit binaries. A problem system here is macOS Catalina (10.15) as as of that
+version macOS no longer supports 32-bit binaries.
+
+There are numerous example entries that require 32-bit binaries. We have tried
+to note these in both the respective Makefiles and README.md files but it is
+possible that some were missed. These entries are very likely in the
+[bugs.md](/bugs.md) file and we welcome any help in making an alternate version
+for 64-bit systems. Many were fixed to work with modern systems but some are
+supposed to only work with 32-bit systems so any updated version of these
+entries should be an alternate version.
+
+## Q: Under macOS I can't compile some entries and/or they don't work right. Why?
+
+If the entry requires gcc and you did not explicitly install gcc in macOS you
+will not be able to run or use these entries. This is because macOS gcc is
+actually clang, even `/usr/bin/gcc`.
+
+## Q: I can't get XYZZY entry to compile with clang. What can I do?
+
+Although we have fixed numerous entries to work with clang (sometimes in an alt
+version but usually in the program itself) there are some that simply cannot be
+fixed or if they are fixable they have not yet been fixed (we are working on
+this but other things have to be done too and all on free time).
+
+This is because clang has some defects where the args of main() are required to
+be a specific type and some versions of clang allow only 1, 2 or 3 args, not 4,
+to main(). In the case of types of args many were changed to the right type and
+then what was main() became another function of the original main() type.
+
+At the same time some entries are not designed to work with clang. There might
+be alternate code added at some point but as above this depends on free time and
+other things that have to be done plus remembering to do it.
 
 ## Q: After running a program my terminal is all messed up! How do I restore my terminal?
 

thanks-for-fixes.md

@@ -736,8 +736,8 @@ calls which has the four args.
 Cody fixed a segfault in this program that prevented it from working right but
 he notes it hangs in macOS. This is because some compilers compile it into an
 infinite loop and this was documented by the judges. It works fine in linux if
-using gcc but macOS, having only clang by default (even the gcc binary) will not
-work.
+using gcc but macOS, having only clang by default (even the gcc binary
+`/usr/bin/gcc`) will not work.
 
 
 ## [1996/dalbec](1996/dalbec/dalbec.c) ([README.md](1996/dalbec/README.md]))
@@ -897,8 +897,9 @@ other version in.
 Cody fixed both the supplementary program and the program itself (both of which
 segfaulted and once that was fixed only the binary was modified; it was not run
 but according to the author's remarks it should be executed). He managed to do
-this with linux but it will not work with macOS (see [bugs.md](/bugs.md) for why
-this is); _this is **not** a bug, it's a feature_ inherent in what it does!
+this with linux but it will not work with macOS Catalina (10.15). See
+[bugs.md](/bugs.md) for why this is); _this is **not** a bug, it's a feature_
+inherent in what it does!
 
 Below is what it took to fix.