Specifying Subprocesses And The Switches To Pass To Them - Red Hat ENTERPRISE LINUX 3 - USING GCC Using Instructions

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The compiler driver program runs one or more of the subprograms
as a prefix for each program it tries to run, both with and without
prefix
(refer to Section 4.16 Specifying Target Machine and Compiler Version).
For each subprogram to be run, the compiler driver first tries the
name is not found, or if
/usr/lib/gcc/
that is found, the unmodified program name is searched for using the directories specified in
your environment variable.
PATH
The compiler will check to see if the path provided by the
it will add a directory separator character at the end of the path.
prefixes that effectively specify directory names also apply to libraries in the linker, because
-B
the compiler translates these options into
files in the preprocessor, because the compiler translates these options into
for the preprocessor. In this case, the compiler appends
The run-time support file
is not found there, the two standard prefixes above are tried, and that is all. The file is left out of
the link if it is not found by those means.
Another way to specify a prefix much like the
GCC_EXEC_PREFIX
As a special kludge, if the path provided by
range 0 to 9, then it will be replaced by
compiler.
-specs=
file
Process after the compiler reads in the standard
file
that the driver program uses when determining what switches to pass to
gcc
, , etc. More than one
as ld
processed in order, from left to right.

4.15. Specifying subprocesses and the switches to pass to them

is a driver program. It performs its job by invoking a sequence of other programs to do the work
gcc
of compiling, assembling and linking. GCC interprets its command-line parameters and uses these to
deduce which programs it should invoke, and which command-line options it ought to place on their
command lines. This behavior is controlled by spec strings. In most cases there is one spec string for
each program that GCC can invoke, but a few programs have multiple spec strings to control their
behavior. The spec strings built into GCC can be overridden by using the
switch to specify a spec file.
Spec files are plaintext files that are used to construct spec strings. They consist of a sequence of
directives separated by blank lines. The type of directive is determined by the first non-whitespace
character on the line and it can be one of the following:
%
command
Issues a
command
%include
file
Search for
was not specified, the driver tries two standard prefixes, which are
-B
and
/usr/local/lib/gcc-lib/
libgcc.a
. Refer to Section 4.19 Environment Variables Affecting GCC.
-specs=
to the spec file processor. The commands that can appear here are:
and insert its text at the current point in the specs file.
file
Chapter 4. GCC Command Options
. If neither of those results in a file name
-B
options for the linker. They also apply to includes
-L
include
can also be searched for using the
prefix is to use the environment variable
-B
is
-B [dir/]stage
. This is to help with boot-strapping the
[dir/]include
specs
can be specified on the command line, and they are
file
, ,
cpp cc1 as
machine
prefix, if any. If that
-B
refers to a directory, and if necessary
-isystem
to the prefix.
prefix, if needed. If it
-B
, where is a number in the
/ N
N
file, in order to override the defaults
cc1
-specs=
and . It tries
ld
/ /
version
options
, ,
cc1plus
command-line