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Compiler Command-line Options
• -Onum on page 2-96.
2.1.78 --global_reg=reg_name[,reg_name,...]
This option treats the specified register names as fixed registers.
Syntax
--global_reg=reg_name[,reg_name,...]
Where reg_name is the APCS or TPCS name of the register, denoted by an integer value
in the range 1 to 8.
Register names 1 to 8 map sequentially onto registers r4 to r11.
Restrictions
This option has the same restrictions as the __global_reg storage class specifier.
Example
--global_reg=1,4,5 // reserve registers r4, r7 and r8 respectively.
See also
• __global_reg on page 4-7
• ARM Software Development Toolkit Reference Guide.
2.1.79 --gnu
This option enables the GNU compiler extensions supported by the ARM compiler. The
version of GCC the extensions are compatible with can be determined by inspecting the
predefined macros __GNUC__ and __GNUC_MINOR__.
See also
• --c90 on page 2-22
• --c99 on page 2-22
• --cpp on page 2-30
• --gnu_defaults on page 2-68
• --strict, --no_strict on page 2-119
• GNU language extensions on page 3-25
• Compiler predefines on page 4-198.
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