ARM Compiler toolchain Using the Linker - ARM Information Center

Using scatter files
Example 8-23 Position-independent code
LR_1 0x010000 PI ; The first load region is at 0x010000.
{
ER_RO +0 ; The PI attribute is inherited from parent.
; The default execution address is 0x010000, but the code can be moved.
{
* (+RO) ; All the RO sections go here.
}
ER_RW +0 ABSOLUTE ; PI attribute is overridden by ABSOLUTE.
{
* (+RW) ; The RW sections are placed next. They cannot be moved.
}
ER_ZI +0 ; ER_ZI region placed after ER_RW region.
{
* (+ZI) ; All the ZI sections are placed consecutively here.
}
}
8.38.2 See also
ER_RO, the RO execution region, inherits the PI attribute from the load region LR_1. The next
execution region, ER_RW, is marked as ABSOLUTE and uses the +offset form of base designator.
This prevents ER_RW from inheriting the PI attribute from ER_RO. Also, because the ER_ZI region
has an offset of +0, it inherits the ABSOLUTE attribute from the ER_RW region.
Concepts
Linker Reference:
• About load region descriptions on page 4-5
• Considerations when using a relative address +offset for load regions on page 4-16
• Considerations when using a relative address +offset for execution regions on page 4-17.
Reference
Linker Reference:
• --reloc on page 2-132
• --ro_base=address on page 2-135
• --ropi on page 2-136
• Load region attributes on page 4-7.
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