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─────/PACKC Option──────────────────────────────────────────────────────────
 
     Syntax:  /PACKC[ODE][:number]
 
     The /PACKC option turns on code-segment packing.
 
     LINK packs code segments by grouping together neighboring code
     segments that have the same attributes. Segments in the same group
     are assigned the same segment address; offset addresses are
     adjusted accordingly. All items have the same physical address
     whether or not the /PACKC option is used. However, /PACKC changes
     the segment and offset addresses so that all items in a group
     share the same segment.
 
     Specify <number> to set the maximum size of groups formed by
     /PACKC. The default without <number> or /PACKC is 64K - 36. When
     LINK cannot add another segment without exceeding <number>, it
     forms a new group.
     See: ◄Entering Numeric Arguments►
 
     /PACKC produces slightly faster and more compact code. It affects
     only programs with multiple code segments.
 
     Code-segment packing provides more opportunities for far-call
     optimization (enabled with the /FARCALL option). /PACKC and
     /FARCALL together produce faster and more compact code. However,
     this combination is not recommended for Windows applications.
     See: ◄/FARCALL Option►
 
     Code-segment packing is off by default. However, if an environment
     variable (such as LINK or FL) includes /PACKC, you can use the
     /NOPACKC option to override /PACKC. /NOPACKC overrides /PACKC if
     /PACKC is specified first.
     See: ◄LINK Environment Variable►
          ◄/NOPACKC Option►
 
     Caution
 
     /PACKC can be unsafe when used with assembly-language programs
     that make assumptions about the relative order of code segments.
 
     For example, the following assembly code attempts to calculate the
     distance between CSEG1 and CSEG2. This produces incorrect results
     when used with /PACKC, because /PACKC causes the two segments to
     share the same segment address. The procedure always returns zero.
 
     CSEG1      SEGMENT PUBLIC 'CODE'
     .
     .
     .
     CSEG1      ENDS
 
     CSEG2      SEGMENT PARA PUBLIC 'CODE'
                ASSUME  cs:CSEG2
 
     ; Return the length of CSEG1 in AX.
 
     codesize   PROC  NEAR
                mov   ax, CSEG2  ; Load para address of CSEG1
                sub   ax, CSEG1  ; Load para address of CSEG2
                mov   cx, 4      ; Load count
                shl   ax, cl     ; convert distance from paragraphs
                                 ;  to bytes
     codesize   ENDP
     CSEG2      ENDS
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