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Chapter 13. ARM Dependent Features

 mthumb

This option specifies that the assembler should start assembling Thumb instructions; that is, it

should behave as though the file starts with a

.code 16

directive.

 mthumb interwork

This option specifies that the output generated by the assembler should be marked as supporting

interworking.

 mapcs [26|32]

This option specifies that the output generated by the assembler should be marked as supporting

the indicated version of the Arm Procedure. Calling Standard.

 matpcs

This option specifies that the output generated by the assembler should be marked as supporting

the Arm/Thumb Procedure Calling Standard. If enabled this option will cause the assembler to

create an empty debugging section in the object file called .arm.atpcs. Debuggers can use this to

determine the ABI being used by.

 mapcs float

This indicates the floating point variant of the APCS should be used. In this variant floating point

arguments are passed in FP registers rather than integer registers.

 mapcs reentrant

This indicates that the reentrant variant of the APCS should be used. This variant supports posi 

tion independent code.

 mfloat abi=abi

This option specifies that the output generated by the assembler should be marked as using spec 

ified floating point ABI. The following values are recognized:

soft

,

softfp

and

hard

.

 meabi=ver

This option specifies which EABI version the produced object files should conform to. The fol 

lowing values are recognised:

gnu

and

3

.

 EB

This option specifies that the output generated by the assembler should be marked as being

encoded for a big endian processor.

 EL

This option specifies that the output generated by the assembler should be marked as being

encoded for a little endian processor.

 k

This option specifies that the output of the assembler should be marked as position independent

code (PIC).