Modifying The Data Sections That Contain Stack Unwinding Information; Creating The Mcb - HP eld Manual

Other eld Processing
there are multiple -strip options, the temporary filename specified by -temp_o
applies to all of them.
The ELF symbol table can never be stripped from a linkfile, and the .dynsym and
.dynsym.gblzd sections can never be stripped from a loadfile, because they are
needed by the linker and/or runtime loader.
Modifying the Data Sections that Contain Stack Unwinding
Information
Linkfiles may contain an unwind function section, an unwind information section, and a
relocation table section for that unwind function section. The linker concatenates these
sections when creating another linkfile. The linker similarly concatenates the
information in .procinfo and .procnames sections.
When building a loadfile, the linker creates an unwind function section, unwind
information section, and string space. The format of the unwind function section in a
loadfile is different from the format that it has in a linkfile, containing additional
information that the linker obtains from the .procinfo and .procnames sections of its
input linkfiles.
If there were multiple copies of procedures, the information about unused copies is
omitted from the .procinfo and unwind function sections of linkfiles, and from the
unwind function sections of loadfiles. In the linkfile case, that also means doing
something about the corresponding relocation table entries.

Creating the MCB

The linker creates the MCB ("master control block") as additional data in the .data
section. The internal name of the MCB is _MCB (one underscore), so this name can be
used to reference the MCB. The linker only creates the MCB if it is building a program,
and only if there is a reference to the symbol named _MCB.
symbol named _MCB is defined in any of the linker's input object files, regardless of
the type of file the linker is creating.
Two linker options that specifically affect the value placed into the MCB are
-ansistreams and -nostdfiles. The value that the linker has decided to place
into the ELF header to describe the floating point type is also reflected in the MCB.
The TNS/E linker considers it an error if either of the above options is specified when
the linker is not creating a program. The option -no_stdfiles is accepted as a
synonym for -nostdfiles.
Further information on the MCB may be found in
page A-14.
Modifying the Data Sections that Contain Stack
The MCB (Master Control Block)
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Unwinding Information
reports an error if a
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