How to get anchors to onlinedocs that can be used in external documents?

[Georg-Johann Lay <avr at gjlay dot de>]

How to add an anchor to one of the onlinedocs texi documents?

Suppose I'd like to add an HTML anchor to one of the onlinedocs, for example to 
link it from the gcc release notes.

Currently the only anchors are either auto-generated and contain some hashes 
(hence not usable from external documents) or are trivial like:


x86-Windows-Options.html#x86-Windows-Options
Submodel-Options.html#Submodel-Options
x86-transactional-memory-intrinsics.html#x86-transactional-memory-intrinsics
...

and are always pointing to the top of the respective HTML page.

How can I get an anchor to, say, a subsection without fragmenting the 
respective HTML document into dozens of individual documents and thereby 
changing the document layout, which is not what I want.

Examples as listed in the GCC onlindocs "Table of Contents":

- 3.17.1.1 -march and -mcpu Feature Modifiers
- 3.17.5.1 EIND and Devices with More Than 128 Ki Bytes of Flash
- 6.16.4 SPU Named Address Spaces
- 6.43.2.8 x86 Floating-Point asm Operands

All these entries in the TOC don't link to the indicated place but to the
respective document's header, e.g. "x86 Floating-Point asm Operands" does not 
forward to that section but to "Extended-Asm.html#Extended-Asm" which contains 
9 subsections.


Johann