For any given input file, the file name suffix determines what kind of compilation is done:
file.c
C source code which must be preprocessed.
file.i
C source code which should not be preprocessed.
file.ii
C++ source code which should not be preprocessed.
file.m
Objective-C source code. Note that you must link with the libobjc library to make an Objective-C
program work.
file.mi
Objective-C source code which should not be preprocessed.
file.mm
file.M
Objective-C++ source code. Note that you must link with the libobjc library to make an Objective-C++
program work. Note that .M refers to a literal capital M.
file.mii
Objective-C++ source code which should not be preprocessed.
file.h
: C, C++, Objective-C or Objective-C++ header file to be turned into a precompiled header.
file.cc
file.cp
file.cxx
file.cpp
file.CPP
file.c++
file.C
C++ source code which must be preprocessed. Note that in .cxx, the last two letters must both be
literally x. Likewise, .C refers to a literal capital C.
file.mm
file.M
Objective-C++ source code which must be preprocessed.
file.mii
Objective-C++ source code which should not be preprocessed.
file.hh
file.H
C++ header file to be turned into a precompiled header.
file.f
file.for
file.FOR
Fixed form Fortran source code which should not be preprocessed.
file.F
file.fpp
file.FPP
Fixed form Fortran source code which must be preprocessed (with the traditional preprocessor).
file.f90
file.f95
Free form Fortran source code which should not be preprocessed.
file.F90
: file.F95
Free form Fortran source code which must be preprocessed (with the traditional preprocessor).
file.ads
Ada source code file which contains a library unit declaration (a declaration of a package, subpro-
gram, or generic, or a generic instantiation), or a library unit renaming declaration (a package,
generic, or subprogram renaming declaration). Such files are also called specs.
file.adb
Ada source code file containing a library unit body (a subprogram or package body). Such files are
also called bodies.
file.s
Assembler code.
file.S
Assembler code which must be preprocessed.
other
An object file to be fed straight into linking. Any file name with no recognized suffix is treated
this way.
You can specify the input language explicitly with the -x option:
-x language
Specify explicitly the language for the following input files (rather than letting the compiler
choose a default based on the file name suffix). This option applies to all following input files
until the next -x option. Possible values for language are:
c c-header c-cpp-output
c++ c++-header c++-cpp-output
objective-c objective-c-header objective-c-cpp-output
objective-c++ objective-c++-header objective-c++-cpp-output
assembler assembler-with-cpp
ada
f95 f95-cpp-input
java
treelang
-x none
Turn off any specification of a language, so that subsequent files are handled according to their
file name suffixes (as they are if -x has not been used at all).
-pass-exit-codes
Normally the gcc program will exit with the code of 1 if any phase of the compiler returns a non-suc-
cess return code. If you specify -pass-exit-codes, the gcc program will instead return with numeri-
cally highest error produced by any phase that returned an error indication.
If you only want some of the stages of compilation, you can use -x (or filename suffixes) to tell gcc
where to start, and one of the options -c, -S, or -E to say where gcc is to stop. Note that some combinations (for example, -x cpp-output -E) instruct gcc to do nothing at all.
-c Compile or assemble the source files, but do not link. The linking stage simply is not done. The
ultimate output is in the form of an object file for each source file.
By default, the object file name for a source file is made by replacing the suffix .c, .i, .s, etc.,
with .o.
Unrecognized input files, not requiring compilation or assembly, are ignored.
-S Stop after the stage of compilation proper; do not assemble. The output is in the form of an assem-
bler code file for each non-assembler input file specified.
By default, the assembler file name for a source file is made by replacing the suffix .c, .i, etc.,
with .s.
Input files that don?. require compilation are ignored.
-E Stop after the preprocessing stage; do not run the compiler proper. The output is in the form of
preprocessed source code, which is sent to the standard output.
Input files which don?. require preprocessing are ignored.
-o file
Place output in file file. This applies regardless to whatever sort of output is being produced,
whether it be an executable file, an object file, an assembler file or preprocessed C code.
If -o is not specified, the default is to put an executable file in a.out, the object file for
source.suffix in source.o, its assembler file in source.s, a precompiled header file in source.suf-
fix.gch, and all preprocessed C source on standard output.
-v Print (on standard error output) the commands executed to run the stages of compilation. Also print
the version number of the compiler driver program and of the preprocessor and the compiler proper.
-###
Like -v except the commands are not executed and all command arguments are quoted. This is useful
for shell scripts to capture the driver-generated command lines.
-pipe
Use pipes rather than temporary files for communication between the various stages of compilation.
This fails to work on some systems where the assembler is unable to read from a pipe; but the GNU
assembler has no trouble.
-combine
If you are compiling multiple source files, this option tells the driver to pass all the source files
to the compiler at once (for those languages for which the compiler can handle this). This will
allow intermodule analysis (IMA) to be performed by the compiler. Currently the only language for
which this is supported is C. If you pass source files for multiple languages to the driver, using
this option, the driver will invoke the compiler(s) that support IMA once each, passing each compiler
all the source files appropriate for it. For those languages that do not support IMA this option
will be ignored, and the compiler will be invoked once for each source file in that language. If you
use this option in conjunction with -save-temps, the compiler will generate multiple pre-processed
files (one for each source file), but only one (combined) .o or .s file.
阅读(906) | 评论(0) | 转发(0) |
