diff options
Diffstat (limited to 'ld/ld.texi')
| -rw-r--r-- | ld/ld.texi | 70 |
1 files changed, 69 insertions, 1 deletions
@@ -31,6 +31,7 @@ @set MSP430 @set NDS32 @set NIOSII +@set PDP11 @set POWERPC @set POWERPC64 @set Renesas @@ -3260,7 +3261,7 @@ an error. @kindex --compact-branches @item --compact-branches @kindex --no-compact-branches -@item --compact-branches +@itemx --no-compact-branches These options control the generation of compact instructions by the linker in the PLT entries for MIPS R6. @@ -3269,6 +3270,73 @@ in the PLT entries for MIPS R6. @c man end @end ifset + +@ifset PDP11 +@subsection Options specific to PDP11 targets + +@c man begin OPTIONS + +For the pdp11-aout target, three variants of the output format can be +produced as selected by the following options. The default variant +for pdp11-aout is the @samp{--omagic} option, whereas for other +targets @samp{--nmagic} is the default. The @samp{--imagic} option is +defined only for the pdp11-aout target, while the others are described +here as they apply to the pdp11-aout target. + +@table @gcctabopt + +@kindex -N +@item -N +@kindex --omagic +@itemx --omagic + +Mark the output as @code{OMAGIC} (0407) in the @file{a.out} header to +indicate that the text segment is not to be write-protected and +shared. Since the text and data sections are both readable and +writable, the data section is allocated immediately contiguous after +the text segment. This is the oldest format for PDP11 executable +programs and is the default for @command{ld} on PDP11 Unix systems +from the beginning through 2.11BSD. + +@kindex -n +@item -n +@kindex --nmagic +@itemx --nmagic + +Mark the output as @code{NMAGIC} (0410) in the @file{a.out} header to +indicate that when the output file is executed, the text portion will +be read-only and shareable among all processes executing the same +file. This involves moving the data areas up to the first possible 8K +byte page boundary following the end of the text. This option creates +a @emph{pure executable} format. + +@kindex -z +@item -z +@kindex --imagic +@itemx --imagic + +Mark the output as @code{IMAGIC} (0411) in the @file{a.out} header to +indicate that when the output file is executed, the program text and +data areas will be loaded into separate address spaces using the split +instruction and data space feature of the memory management unit in +larger models of the PDP11. This doubles the address space available +to the program. The text segment is again pure, write-protected, and +shareable. The only difference in the output format between this +option and the others, besides the magic number, is that both the text +and data sections start at location 0. The @samp{-z} option selected +this format in 2.11BSD. This option creates a @emph{separate +executable} format. + +@kindex --no-omagic +@item --no-omagic + +Equivalent to @samp{--nmagic} for pdp11-aout. + +@end table + +@c man end +@end ifset + @ifset UsesEnvVars @node Environment @section Environment Variables |