+Add some additional characters to the string table in order to
+compensate for a wrong boundcheck in some specific version of the
+darkplaces engine.
+.TP
+.B -fadjust-vector-fields
+When assigning to field pointers of type \fI.vector\fR the common
+behaviour in compilers like \fIfteqcc\fR is to only assign the
+x-component of the pointer. This means that you can use the vector as
+such, but you cannot use its y and z components directly. This flag
+fixes this behaviour. Before using it make sure your code does not
+depend on the buggy behaviour.
+.TP
+.B -fftepp
+Enable a partially fteqcc-compatible preprocessor. It supports all the
+features used in the Xonotic codebase. If you need more, write a
+ticket.
+.TP
+.B -fftepp-predefs
+Enable some predefined macros. This only works in combination with
+\'-fftepp' and is currently not included by '-std=fteqcc'. The
+following macros will be added:
+.in +4
+.nf
+__LINE__
+__FILE__
+__COUNTER__
+__COUNTER_LAST__
+__RANDOM__
+__RANDOM_LAST__
+__DATE__
+__TIME__
+.fi
+.in
+Note that fteqcc also defines __NULL__ which is not implemented yet.
+(See -funtyped-nil about gmqcc's alternative to __NULL__).
+.TP
+.B -frelaxed-switch
+Allow switch cases to use non constant variables.
+.TP
+.B -fshort-logic
+Perform early out in logical AND and OR expressions. The final result
+will be either a 0 or a 1, see the next flag for more possibilities.
+.TP
+.B -fperl-logic
+In many languages, logical expressions perform early out in a special
+way: If the left operand of an AND yeilds true, or the one of an OR
+yields false, the complete expression evaluates to the right side.
+Thus \fItrue && 5\fI evaluates to 5 rather than 1.
+.TP
+.B -ftranslatable-strings
+Enable the underscore intrinsic: Using \fI_("A string constant")\fR
+will cause the string immediate to get a name with a "dotranslate_"
+prefix. The darkplaces engine recognizes these and translates them in
+a way similar to how gettext works.
+.TP
+.B -finitialized-nonconstants
+Don't implicitly convert initialized variables to constants. With this
+flag, the \fIconst\fR keyword is required to make a constant.
+.TP
+.B -fassign-function-types
+If this flag is not set, (and it is set by default in the qcc and
+fteqcc standards), assigning function pointers of mismatching
+signatures will result in an error rather than a warning.
+.TP
+.B -flno
+Produce a linenumber file along with the output .dat file.
+.TP
+.B -fcorrect-ternary
+Use C's operator precedence for ternary expressions. Unless your code
+depends on fteqcc-compatible behaviour, you'll want to use thi
+soption.
+.TP
+.B -fsingle-vector-defs
+Normally vectors generate 4 defs, once for the vector, and once for
+its components with _x, _y, _z suffixes. This option
+prevents components from being listed.
+.TP
+.B -fcorrect-logic
+Most QC compilers translate if(a_vector) directly as an IF on the
+vector, which means only the x-component is checked. This causes
+vectors to be cast to actual booleans via a NOT_V and, if necessary, a
+NOT_F chained to it.
+.in +4
+.nf
+if (a_vector) // becomes
+if not(!a_vector)
+// likewise
+a = a_vector && a_float // becomes
+a = !!a_vector && a_float
+.fi
+.in
+.TP
+.B -ftrue-empty-strings
+An empty string is considered to be true everywhere. The NOT_S
+instruction usually considers an empty string to be false, this option
+effectively causes the unary not in strings to use NOT_F instead.
+.TP
+.B -ffalse-empty-strings
+An empty string is considered to be false everywhere. This means loops
+and if statements which depend on a string will perform a NOT_S
+instruction on the string before using it.
+.TP
+.B -futf8
+Enable utf8 characters. This allows utf-8 encoded character constants,
+and escape sequence codepoints in the valid utf-8 range. Effectively
+enabling escape sequences like '\\{x2211}'.
+.TP
+.B -fbail-on-werror
+When a warning is treated as an error, and this option is set (which
+it is by default), it is like any other error and will cause
+compilation to stop. When disabling this flag by using
+\-fno-bail-on-werror, compilation will continue until the end, but no
+output is generated. Instead the first such error message's context is
+shown.
+.TP
+.B -floop-labels
+Allow loops to be labeled, and allow 'break' and 'continue' to take an
+optional label to decide which loop to actually jump out of or
+continue.
+.sp
+.in +4
+.nf
+for :outer (i = 0; i < n; ++i) {
+ while (inner) {
+ ...;
+ if (something)
+ continue outer;
+ }
+}
+.fi
+.in
+.TP
+.B -funtyped-nil
+Adds a global named 'nil' which is of no type and can be assigned to
+anything. No typechecking will be performed on assignments. Assigning
+to it is forbidden, using it in any other kind of expression is also
+not allowed.
+.sp
+Note that this is different from fteqcc's __NULL__: In fteqcc,
+__NULL__ maps to the integer written as '0i'. It's can be assigned to
+function pointers and integers, but it'll error about invalid
+instructions when assigning it to floats without enabling the FTE
+instruction set. There's also a bug which allows it to be assigned to
+vectors, for which the source will be the global at offset 0, meaning
+the vector's y and z components will contain the OFS_RETURN x and y
+components.
+.sp
+In that gmqcc the nil global is an actual global filled with zeroes,
+and can be assigned to anything including fields, vectors or function
+pointers, and they end up becoming zeroed.
+.TP
+.B -fpermissive
+Various effects, usually to weaken some conditions.
+.RS
+.IP "with -funtyped-nil"
+Allow local variables named 'nil'. (This will not allow declaring a
+global of that name.)
+.RE
+.SH OPTIMIZATIONS
+.TP
+.B -Opeephole
+Some general peephole optimizations. For instance the code `a = b + c`
+typically generates 2 instructions, an ADD and a STORE. This
+optimization removes the STORE and lets the ADD write directly into A.
+.TP
+.B -Otail-recursion
+Tail recursive function calls will be turned into loops to avoid the
+overhead of the CALL and RETURN instructions.
+.TP
+.B -Ooverlap-locals
+Make all functions which use neither local arrays nor have locals
+which are seen as possibly uninitialized use the same local section.
+This should be pretty safe compared to other compilers which do not
+check for uninitialized values properly. The problem is that there's
+QC code out there which really doesn't initialize some values. This is
+fine as long as this kind of optimization isn't used, but also, only
+as long as the functions cannot be called in a recursive manner. Since
+it's hard to know whether or not an array is actually fully
+initialized, especially when initializing it via a loop, we assume
+functions with arrays to be too dangerous for this optimization.
+.TP
+.B -Olocal-temps
+This promotes locally declared variables to "temps". Meaning when a
+temporary result of an operation has to be stored somewhere, a local
+variable which is not 'alive' at that point can be used to keep the
+result. This can reduce the size of the global section.
+This will not have declared variables overlap, even if it was
+possible.
+.TP
+.B -Oglobal-temps
+Causes temporary values which do not need to be backed up on a CALL to
+not be stored in the function's locals-area. With this, a CALL to a
+function may need to back up fewer values and thus execute faster.
+.TP
+.B -Ostrip-constant-names
+Don't generate defs for immediate values or even declared constants.
+Meaning variables which are implicitly constant or qualified as such
+using the 'const' keyword.
+.TP
+.B -Ooverlap-strings
+Aggressively reuse strings in the string section. When a string should
+be added which is the trailing substring of an already existing
+string, the existing string's tail will be returned instead of the new
+string being added.
+
+For example the following code will only generate 1 string:
+
+.in +4
+.nf
+print("Hell you!\\n");
+print("you!\\n"); // trailing substring of "Hello you!\\n"
+.fi
+.in
+There's however one limitation. Strings are still processed in order,
+so if the above print statements were reversed, this optimization
+would not happen.
+.TP
+.B -Ocall-stores
+By default, all parameters of a CALL are copied into the
+parameter-globals right before the CALL instructions. This is the
+easiest and safest way to translate calls, but also adds a lot of
+unnecessary copying and unnecessary temporary values. This
+optimization makes operations which are used as a parameter evaluate
+directly into the parameter-global if that is possible, which is when
+there's no other CALL instruction in between.
+.TP
+.B -Ovoid-return
+Usually an empty RETURN instruction is added to the end of a void
+typed function. However, additionally after every function a DONE
+instruction is added for several reasons. (For example the qcvm's
+disassemble switch uses it to know when the function ends.). This
+optimization replaces that last RETURN with DONE rather than adding
+the DONE additionally.