gcc, the GNU linker, and the glibc dynamic linker cooperate to implement an idea called read-only relocations, or relro. This permits the linker to designate a part of an executable or (more commonly) a shared library as being read-only after dynamic relocations have been applied. This may be used for read-only global variables which are […]
The GNU linker has a -z combreloc option, which is enabled by default (it can be turned off via -z nocombreloc). I just implemented this in gold as well. This option directs the linker to sort the dynamic relocations. The sorting is done in order to optimize the dynamic linker. The dynamic linker in glibc […]
As I continue trying to build the kernel with gold, I’ve had to copy several features from the GNU linker to gold. Historically, the GNU linker implemented the -R option to mean that it should only use the symbols found in the named object; the object should not actually be included in the output file. […]
This will be my last blog posting on linkers for the time being. Tomorrow my blog will return to its usual trivialities. People who are specifically interested in linker information are warned to stop reading with this post. I’ll close the series with a short update on gold, the new linker I’ve been working on. […]
I’ve pretty much run out of linker topics. Unless I think of something new, I’ll make tomorrow’s post be the last one, for a total of 20. __start and __stop Symbols A quick note about another GNU linker extension. If the linker sees a section in the output file which can be part of a […]