Compiling and Linking the Driver

Compile each driver source file and link the resulting object files into a driver module. The example below shows a driver called xx that has two C-language source files and generates a driver module xx. The driver created in this example is intended for the 32–bit kernel:

% cc -D_KERNEL -c xx1.c
% cc -D_KERNEL -c xx2.c
% ld -r -o xx xx1.o xx2.o

The _KERNEL symbol must be defined while compiling kernel (driver) code. No other symbols (such as sun4m) should be defined, aside from driver private symbols. DEBUG can also be defined to enable any calls to assert(9F). There is no need to use the -I flag for the standard headers.

Drivers intended for the 64-bit SPARC kernel should specify the -xarch=v9 option. Use the following compile line:

% cc -D_KERNEL -xarch=v9 -c xx1.c

After the driver is stable, optimization flags can be used to build a production quality driver. For the Sun WorkShop™ Compilers C, the normal -O flag, or its equivalent -xO3, can be used. Note that -xO3 is the highest level of optimization device drivers should use (see cc(1)).

The following compile line was used to create 64–bit SPARC drivers provided with the Solaris 9 operating environment:

% cc -D_KERNEL -xcg92 -xarch=v9 -xcode=abs32 -xO3 -c xx1.c

Where -xcg92 refers to the code generator, and the use of -xcode=abs32 leads to more compact code.

Running ld -r is necessary even if there is only one object module.