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(stabs.info)Function Types

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Function Types
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   Various types can be defined for function variables.  These types are
not used in defining functions (Note: Procedures); they are used for
things like pointers to functions.

   The simple, traditional, type is type descriptor `f' is followed by
type information for the return type of the function, followed by a
semicolon.

   This does not deal with functions for which the number and types of
the parameters are part of the type, as in Modula-2 or ANSI C.  AIX
provides extensions to specify these, using the `f', `F', `p', and `R'
type descriptors.

   First comes the type descriptor.  If it is `f' or `F', this type
involves a function rather than a procedure, and the type information
for the return type of the function follows, followed by a comma.  Then
comes the number of parameters to the function and a semicolon.  Then,
for each parameter, there is the name of the parameter followed by a
colon (this is only present for type descriptors `R' and `F' which
represent Pascal function or procedure parameters), type information
for the parameter, a comma, 0 if passed by reference or 1 if passed by
value, and a semicolon.  The type definition ends with a semicolon.

   For example, this variable definition:

     int (*g_pf)();

generates the following code:

     .stabs "g_pf:G24=*25=f1",32,0,0,0
         .common _g_pf,4,"bss"

   The variable defines a new type, 24, which is a pointer to another
new type, 25, which is a function returning `int'.