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diff --git a/gcc/gcc.info-3 b/gcc/gcc.info-3 deleted file mode 100644 index d60f8139c92..00000000000 --- a/gcc/gcc.info-3 +++ /dev/null @@ -1,1198 +0,0 @@ -This is Info file gcc.info, produced by Makeinfo version 1.68 from the -input file gcc.texi. - - This file documents the use and the internals of the GNU compiler. - - Published by the Free Software Foundation 59 Temple Place - Suite 330 -Boston, MA 02111-1307 USA - - Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997 Free -Software Foundation, Inc. - - Permission is granted to make and distribute verbatim copies of this -manual provided the copyright notice and this permission notice are -preserved on all copies. - - Permission is granted to copy and distribute modified versions of -this manual under the conditions for verbatim copying, provided also -that the sections entitled "GNU General Public License," "Funding for -Free Software," and "Protect Your Freedom--Fight `Look And Feel'" are -included exactly as in the original, and provided that the entire -resulting derived work is distributed under the terms of a permission -notice identical to this one. - - Permission is granted to copy and distribute translations of this -manual into another language, under the above conditions for modified -versions, except that the sections entitled "GNU General Public -License," "Funding for Free Software," and "Protect Your Freedom--Fight -`Look And Feel'", and this permission notice, may be included in -translations approved by the Free Software Foundation instead of in the -original English. - - -File: gcc.info, Node: Preprocessor Options, Next: Assembler Options, Prev: Optimize Options, Up: Invoking GCC - -Options Controlling the Preprocessor -==================================== - - These options control the C preprocessor, which is run on each C -source file before actual compilation. - - If you use the `-E' option, nothing is done except preprocessing. -Some of these options make sense only together with `-E' because they -cause the preprocessor output to be unsuitable for actual compilation. - -`-include FILE' - Process FILE as input before processing the regular input file. - In effect, the contents of FILE are compiled first. Any `-D' and - `-U' options on the command line are always processed before - `-include FILE', regardless of the order in which they are - written. All the `-include' and `-imacros' options are processed - in the order in which they are written. - -`-imacros FILE' - Process FILE as input, discarding the resulting output, before - processing the regular input file. Because the output generated - from FILE is discarded, the only effect of `-imacros FILE' is to - make the macros defined in FILE available for use in the main - input. - - Any `-D' and `-U' options on the command line are always processed - before `-imacros FILE', regardless of the order in which they are - written. All the `-include' and `-imacros' options are processed - in the order in which they are written. - -`-idirafter DIR' - Add the directory DIR to the second include path. The directories - on the second include path are searched when a header file is not - found in any of the directories in the main include path (the one - that `-I' adds to). - -`-iprefix PREFIX' - Specify PREFIX as the prefix for subsequent `-iwithprefix' options. - -`-iwithprefix DIR' - Add a directory to the second include path. The directory's name - is made by concatenating PREFIX and DIR, where PREFIX was - specified previously with `-iprefix'. If you have not specified a - prefix yet, the directory containing the installed passes of the - compiler is used as the default. - -`-iwithprefixbefore DIR' - Add a directory to the main include path. The directory's name is - made by concatenating PREFIX and DIR, as in the case of - `-iwithprefix'. - -`-isystem DIR' - Add a directory to the beginning of the second include path, - marking it as a system directory, so that it gets the same special - treatment as is applied to the standard system directories. - -`-nostdinc' - Do not search the standard system directories for header files. - Only the directories you have specified with `-I' options (and the - current directory, if appropriate) are searched. *Note Directory - Options::, for information on `-I'. - - By using both `-nostdinc' and `-I-', you can limit the include-file - search path to only those directories you specify explicitly. - -`-undef' - Do not predefine any nonstandard macros. (Including architecture - flags). - -`-E' - Run only the C preprocessor. Preprocess all the C source files - specified and output the results to standard output or to the - specified output file. - -`-C' - Tell the preprocessor not to discard comments. Used with the `-E' - option. - -`-P' - Tell the preprocessor not to generate `#line' directives. Used - with the `-E' option. - -`-M' - Tell the preprocessor to output a rule suitable for `make' - describing the dependencies of each object file. For each source - file, the preprocessor outputs one `make'-rule whose target is the - object file name for that source file and whose dependencies are - all the `#include' header files it uses. This rule may be a - single line or may be continued with `\'-newline if it is long. - The list of rules is printed on standard output instead of the - preprocessed C program. - - `-M' implies `-E'. - - Another way to specify output of a `make' rule is by setting the - environment variable `DEPENDENCIES_OUTPUT' (*note Environment - Variables::.). - -`-MM' - Like `-M' but the output mentions only the user header files - included with `#include "FILE"'. System header files included - with `#include <FILE>' are omitted. - -`-MD' - Like `-M' but the dependency information is written to a file made - by replacing ".c" with ".d" at the end of the input file names. - This is in addition to compiling the file as specified--`-MD' does - not inhibit ordinary compilation the way `-M' does. - - In Mach, you can use the utility `md' to merge multiple dependency - files into a single dependency file suitable for using with the - `make' command. - -`-MMD' - Like `-MD' except mention only user header files, not system - header files. - -`-MG' - Treat missing header files as generated files and assume they live - in the same directory as the source file. If you specify `-MG', - you must also specify either `-M' or `-MM'. `-MG' is not - supported with `-MD' or `-MMD'. - -`-H' - Print the name of each header file used, in addition to other - normal activities. - -`-AQUESTION(ANSWER)' - Assert the answer ANSWER for QUESTION, in case it is tested with a - preprocessing conditional such as `#if #QUESTION(ANSWER)'. `-A-' - disables the standard assertions that normally describe the target - machine. - -`-DMACRO' - Define macro MACRO with the string `1' as its definition. - -`-DMACRO=DEFN' - Define macro MACRO as DEFN. All instances of `-D' on the command - line are processed before any `-U' options. - -`-UMACRO' - Undefine macro MACRO. `-U' options are evaluated after all `-D' - options, but before any `-include' and `-imacros' options. - -`-dM' - Tell the preprocessor to output only a list of the macro - definitions that are in effect at the end of preprocessing. Used - with the `-E' option. - -`-dD' - Tell the preprocessing to pass all macro definitions into the - output, in their proper sequence in the rest of the output. - -`-dN' - Like `-dD' except that the macro arguments and contents are - omitted. Only `#define NAME' is included in the output. - -`-trigraphs' - Support ANSI C trigraphs. The `-ansi' option also has this effect. - -`-Wp,OPTION' - Pass OPTION as an option to the preprocessor. If OPTION contains - commas, it is split into multiple options at the commas. - - -File: gcc.info, Node: Assembler Options, Next: Link Options, Prev: Preprocessor Options, Up: Invoking GCC - -Passing Options to the Assembler -================================ - - You can pass options to the assembler. - -`-Wa,OPTION' - Pass OPTION as an option to the assembler. If OPTION contains - commas, it is split into multiple options at the commas. - - -File: gcc.info, Node: Link Options, Next: Directory Options, Prev: Assembler Options, Up: Invoking GCC - -Options for Linking -=================== - - These options come into play when the compiler links object files -into an executable output file. They are meaningless if the compiler is -not doing a link step. - -`OBJECT-FILE-NAME' - A file name that does not end in a special recognized suffix is - considered to name an object file or library. (Object files are - distinguished from libraries by the linker according to the file - contents.) If linking is done, these object files are used as - input to the linker. - -`-c' -`-S' -`-E' - If any of these options is used, then the linker is not run, and - object file names should not be used as arguments. *Note Overall - Options::. - -`-lLIBRARY' - Search the library named LIBRARY when linking. - - It makes a difference where in the command you write this option; - the linker searches processes libraries and object files in the - order they are specified. Thus, `foo.o -lz bar.o' searches - library `z' after file `foo.o' but before `bar.o'. If `bar.o' - refers to functions in `z', those functions may not be loaded. - - The linker searches a standard list of directories for the library, - which is actually a file named `libLIBRARY.a'. The linker then - uses this file as if it had been specified precisely by name. - - The directories searched include several standard system - directories plus any that you specify with `-L'. - - Normally the files found this way are library files--archive files - whose members are object files. The linker handles an archive - file by scanning through it for members which define symbols that - have so far been referenced but not defined. But if the file that - is found is an ordinary object file, it is linked in the usual - fashion. The only difference between using an `-l' option and - specifying a file name is that `-l' surrounds LIBRARY with `lib' - and `.a' and searches several directories. - -`-lobjc' - You need this special case of the `-l' option in order to link an - Objective C program. - -`-nostartfiles' - Do not use the standard system startup files when linking. The - standard system libraries are used normally, unless `-nostdlib' or - `-nodefaultlibs' is used. - -`-nodefaultlibs' - Do not use the standard system libraries when linking. Only the - libraries you specify will be passed to the linker. The standard - startup files are used normally, unless `-nostartfiles' is used. - -`-nostdlib' - Do not use the standard system startup files or libraries when - linking. No startup files and only the libraries you specify will - be passed to the linker. - - One of the standard libraries bypassed by `-nostdlib' and - `-nodefaultlibs' is `libgcc.a', a library of internal subroutines - that GNU CC uses to overcome shortcomings of particular machines, - or special needs for some languages. (*Note Interfacing to GNU CC - Output: Interface, for more discussion of `libgcc.a'.) In most - cases, you need `libgcc.a' even when you want to avoid other - standard libraries. In other words, when you specify `-nostdlib' - or `-nodefaultlibs' you should usually specify `-lgcc' as well. - This ensures that you have no unresolved references to internal - GNU CC library subroutines. (For example, `__main', used to - ensure C++ constructors will be called; *note `collect2': - Collect2..) - -`-s' - Remove all symbol table and relocation information from the - executable. - -`-static' - On systems that support dynamic linking, this prevents linking - with the shared libraries. On other systems, this option has no - effect. - -`-shared' - Produce a shared object which can then be linked with other - objects to form an executable. Not all systems support this - option. You must also specify `-fpic' or `-fPIC' on some systems - when you specify this option. - -`-symbolic' - Bind references to global symbols when building a shared object. - Warn about any unresolved references (unless overridden by the - link editor option `-Xlinker -z -Xlinker defs'). Only a few - systems support this option. - -`-Xlinker OPTION' - Pass OPTION as an option to the linker. You can use this to - supply system-specific linker options which GNU CC does not know - how to recognize. - - If you want to pass an option that takes an argument, you must use - `-Xlinker' twice, once for the option and once for the argument. - For example, to pass `-assert definitions', you must write - `-Xlinker -assert -Xlinker definitions'. It does not work to write - `-Xlinker "-assert definitions"', because this passes the entire - string as a single argument, which is not what the linker expects. - -`-Wl,OPTION' - Pass OPTION as an option to the linker. If OPTION contains - commas, it is split into multiple options at the commas. - -`-u SYMBOL' - Pretend the symbol SYMBOL is undefined, to force linking of - library modules to define it. You can use `-u' multiple times with - different symbols to force loading of additional library modules. - - -File: gcc.info, Node: Directory Options, Next: Target Options, Prev: Link Options, Up: Invoking GCC - -Options for Directory Search -============================ - - These options specify directories to search for header files, for -libraries and for parts of the compiler: - -`-IDIR' - Add the directory DIR to the head of the list of directories to be - searched for header files. This can be used to override a system - header file, substituting your own version, since these - directories are searched before the system header file - directories. If you use more than one `-I' option, the - directories are scanned in left-to-right order; the standard - system directories come after. - -`-I-' - Any directories you specify with `-I' options before the `-I-' - option are searched only for the case of `#include "FILE"'; they - are not searched for `#include <FILE>'. - - If additional directories are specified with `-I' options after - the `-I-', these directories are searched for all `#include' - directives. (Ordinarily *all* `-I' directories are used this way.) - - In addition, the `-I-' option inhibits the use of the current - directory (where the current input file came from) as the first - search directory for `#include "FILE"'. There is no way to - override this effect of `-I-'. With `-I.' you can specify - searching the directory which was current when the compiler was - invoked. That is not exactly the same as what the preprocessor - does by default, but it is often satisfactory. - - `-I-' does not inhibit the use of the standard system directories - for header files. Thus, `-I-' and `-nostdinc' are independent. - -`-LDIR' - Add directory DIR to the list of directories to be searched for - `-l'. - -`-BPREFIX' - This option specifies where to find the executables, libraries, - include files, and data files of the compiler itself. - - The compiler driver program runs one or more of the subprograms - `cpp', `cc1', `as' and `ld'. It tries PREFIX as a prefix for each - program it tries to run, both with and without `MACHINE/VERSION/' - (*note Target Options::.). - - For each subprogram to be run, the compiler driver first tries the - `-B' prefix, if any. If that name is not found, or if `-B' was - not specified, the driver tries two standard prefixes, which are - `/usr/lib/gcc/' and `/usr/local/lib/gcc-lib/'. If neither of - those results in a file name that is found, the unmodified program - name is searched for using the directories specified in your - `PATH' environment variable. - - `-B' prefixes that effectively specify directory names also apply - to libraries in the linker, because the compiler translates these - options into `-L' options for the linker. They also apply to - includes files in the preprocessor, because the compiler - translates these options into `-isystem' options for the - preprocessor. In this case, the compiler appends `include' to the - prefix. - - The run-time support file `libgcc.a' can also be searched for using - the `-B' prefix, if needed. If it 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 `-B' prefix is to use - the environment variable `GCC_EXEC_PREFIX'. *Note Environment - Variables::. - -`-specs=FILE' - Process FILE after the compiler reads in the standard `specs' - file, in order to override the defaults that the `gcc' driver - program uses when determining what switches to pass to `cc1', - `cc1plus', `as', `ld', etc. More than one `-specs='FILE can be - specified on the command line, and they are processed in order, - from left to right. - - -File: gcc.info, Node: Target Options, Next: Submodel Options, Prev: Directory Options, Up: Invoking GCC - -Specifying Target Machine and Compiler Version -============================================== - - By default, GNU CC compiles code for the same type of machine that -you are using. However, it can also be installed as a cross-compiler, -to compile for some other type of machine. In fact, several different -configurations of GNU CC, for different target machines, can be -installed side by side. Then you specify which one to use with the -`-b' option. - - In addition, older and newer versions of GNU CC can be installed side -by side. One of them (probably the newest) will be the default, but -you may sometimes wish to use another. - -`-b MACHINE' - The argument MACHINE specifies the target machine for compilation. - This is useful when you have installed GNU CC as a cross-compiler. - - The value to use for MACHINE is the same as was specified as the - machine type when configuring GNU CC as a cross-compiler. For - example, if a cross-compiler was configured with `configure - i386v', meaning to compile for an 80386 running System V, then you - would specify `-b i386v' to run that cross compiler. - - When you do not specify `-b', it normally means to compile for the - same type of machine that you are using. - -`-V VERSION' - The argument VERSION specifies which version of GNU CC to run. - This is useful when multiple versions are installed. For example, - VERSION might be `2.0', meaning to run GNU CC version 2.0. - - The default version, when you do not specify `-V', is the last - version of GNU CC that you installed. - - The `-b' and `-V' options actually work by controlling part of the -file name used for the executable files and libraries used for -compilation. A given version of GNU CC, for a given target machine, is -normally kept in the directory `/usr/local/lib/gcc-lib/MACHINE/VERSION'. - - Thus, sites can customize the effect of `-b' or `-V' either by -changing the names of these directories or adding alternate names (or -symbolic links). If in directory `/usr/local/lib/gcc-lib/' the file -`80386' is a link to the file `i386v', then `-b 80386' becomes an alias -for `-b i386v'. - - In one respect, the `-b' or `-V' do not completely change to a -different compiler: the top-level driver program `gcc' that you -originally invoked continues to run and invoke the other executables -(preprocessor, compiler per se, assembler and linker) that do the real -work. However, since no real work is done in the driver program, it -usually does not matter that the driver program in use is not the one -for the specified target and version. - - The only way that the driver program depends on the target machine is -in the parsing and handling of special machine-specific options. -However, this is controlled by a file which is found, along with the -other executables, in the directory for the specified version and -target machine. As a result, a single installed driver program adapts -to any specified target machine and compiler version. - - The driver program executable does control one significant thing, -however: the default version and target machine. Therefore, you can -install different instances of the driver program, compiled for -different targets or versions, under different names. - - For example, if the driver for version 2.0 is installed as `ogcc' -and that for version 2.1 is installed as `gcc', then the command `gcc' -will use version 2.1 by default, while `ogcc' will use 2.0 by default. -However, you can choose either version with either command with the -`-V' option. - - -File: gcc.info, Node: Submodel Options, Next: Code Gen Options, Prev: Target Options, Up: Invoking GCC - -Hardware Models and Configurations -================================== - - Earlier we discussed the standard option `-b' which chooses among -different installed compilers for completely different target machines, -such as Vax vs. 68000 vs. 80386. - - In addition, each of these target machine types can have its own -special options, starting with `-m', to choose among various hardware -models or configurations--for example, 68010 vs 68020, floating -coprocessor or none. A single installed version of the compiler can -compile for any model or configuration, according to the options -specified. - - Some configurations of the compiler also support additional special -options, usually for compatibility with other compilers on the same -platform. - - These options are defined by the macro `TARGET_SWITCHES' in the -machine description. The default for the options is also defined by -that macro, which enables you to change the defaults. - -* Menu: - -* M680x0 Options:: -* VAX Options:: -* SPARC Options:: -* Convex Options:: -* AMD29K Options:: -* ARM Options:: -* M32R/D Options:: -* M88K Options:: -* RS/6000 and PowerPC Options:: -* RT Options:: -* MIPS Options:: -* i386 Options:: -* HPPA Options:: -* Intel 960 Options:: -* DEC Alpha Options:: -* Clipper Options:: -* H8/300 Options:: -* SH Options:: -* System V Options:: -* V850 Options:: - - -File: gcc.info, Node: M680x0 Options, Next: VAX Options, Up: Submodel Options - -M680x0 Options --------------- - - These are the `-m' options defined for the 68000 series. The default -values for these options depends on which style of 68000 was selected -when the compiler was configured; the defaults for the most common -choices are given below. - -`-m68000' -`-mc68000' - Generate output for a 68000. This is the default when the - compiler is configured for 68000-based systems. - -`-m68020' -`-mc68020' - Generate output for a 68020. This is the default when the - compiler is configured for 68020-based systems. - -`-m68881' - Generate output containing 68881 instructions for floating point. - This is the default for most 68020 systems unless `-nfp' was - specified when the compiler was configured. - -`-m68030' - Generate output for a 68030. This is the default when the - compiler is configured for 68030-based systems. - -`-m68040' - Generate output for a 68040. This is the default when the - compiler is configured for 68040-based systems. - - This option inhibits the use of 68881/68882 instructions that have - to be emulated by software on the 68040. If your 68040 does not - have code to emulate those instructions, use `-m68040'. - -`-m68060' - Generate output for a 68060. This is the default when the - compiler is configured for 68060-based systems. - - This option inhibits the use of 68020 and 68881/68882 instructions - that have to be emulated by software on the 68060. If your 68060 - does not have code to emulate those instructions, use `-m68060'. - -`-m5200' - Generate output for a 520X "coldfire" family cpu. This is the - default when the compiler is configured for 520X-based systems. - -`-m68020-40' - Generate output for a 68040, without using any of the new - instructions. This results in code which can run relatively - efficiently on either a 68020/68881 or a 68030 or a 68040. The - generated code does use the 68881 instructions that are emulated - on the 68040. - -`-m68020-60' - Generate output for a 68060, without using any of the new - instructions. This results in code which can run relatively - efficiently on either a 68020/68881 or a 68030 or a 68040. The - generated code does use the 68881 instructions that are emulated - on the 68060. - -`-mfpa' - Generate output containing Sun FPA instructions for floating point. - -`-msoft-float' - Generate output containing library calls for floating point. - *Warning:* the requisite libraries are not available for all m68k - targets. Normally the facilities of the machine's usual C - compiler are used, but this can't be done directly in - cross-compilation. You must make your own arrangements to provide - suitable library functions for cross-compilation. The embedded - targets `m68k-*-aout' and `m68k-*-coff' do provide software - floating point support. - -`-mshort' - Consider type `int' to be 16 bits wide, like `short int'. - -`-mnobitfield' - Do not use the bit-field instructions. The `-m68000' option - implies `-mnobitfield'. - -`-mbitfield' - Do use the bit-field instructions. The `-m68020' option implies - `-mbitfield'. This is the default if you use a configuration - designed for a 68020. - -`-mrtd' - Use a different function-calling convention, in which functions - that take a fixed number of arguments return with the `rtd' - instruction, which pops their arguments while returning. This - saves one instruction in the caller since there is no need to pop - the arguments there. - - This calling convention is incompatible with the one normally used - on Unix, so you cannot use it if you need to call libraries - compiled with the Unix compiler. - - Also, you must provide function prototypes for all functions that - take variable numbers of arguments (including `printf'); otherwise - incorrect code will be generated for calls to those functions. - - In addition, seriously incorrect code will result if you call a - function with too many arguments. (Normally, extra arguments are - harmlessly ignored.) - - The `rtd' instruction is supported by the 68010, 68020, 68030, - 68040, and 68060 processors, but not by the 68000 or 5200. - -`-malign-int' -`-mno-align-int' - Control whether GNU CC aligns `int', `long', `long long', `float', - `double', and `long double' variables on a 32-bit boundary - (`-malign-int') or a 16-bit boundary (`-mno-align-int'). Aligning - variables on 32-bit boundaries produces code that runs somewhat - faster on processors with 32-bit busses at the expense of more - memory. - - *Warning:* if you use the `-malign-int' switch, GNU CC will align - structures containing the above types differently than most - published application binary interface specifications for the m68k. - - -File: gcc.info, Node: VAX Options, Next: SPARC Options, Prev: M680x0 Options, Up: Submodel Options - -VAX Options ------------ - - These `-m' options are defined for the Vax: - -`-munix' - Do not output certain jump instructions (`aobleq' and so on) that - the Unix assembler for the Vax cannot handle across long ranges. - -`-mgnu' - Do output those jump instructions, on the assumption that you will - assemble with the GNU assembler. - -`-mg' - Output code for g-format floating point numbers instead of - d-format. - - -File: gcc.info, Node: SPARC Options, Next: Convex Options, Prev: VAX Options, Up: Submodel Options - -SPARC Options -------------- - - These `-m' switches are supported on the SPARC: - -`-mno-app-regs' -`-mapp-regs' - Specify `-mapp-regs' to generate output using the global registers - 2 through 4, which the SPARC SVR4 ABI reserves for applications. - This is the default. - - To be fully SVR4 ABI compliant at the cost of some performance - loss, specify `-mno-app-regs'. You should compile libraries and - system software with this option. - -`-mfpu' -`-mhard-float' - Generate output containing floating point instructions. This is - the default. - -`-mno-fpu' -`-msoft-float' - Generate output containing library calls for floating point. - *Warning:* the requisite libraries are not available for all SPARC - targets. Normally the facilities of the machine's usual C - compiler are used, but this cannot be done directly in - cross-compilation. You must make your own arrangements to provide - suitable library functions for cross-compilation. The embedded - targets `sparc-*-aout' and `sparclite-*-*' do provide software - floating point support. - - `-msoft-float' changes the calling convention in the output file; - therefore, it is only useful if you compile *all* of a program with - this option. In particular, you need to compile `libgcc.a', the - library that comes with GNU CC, with `-msoft-float' in order for - this to work. - -`-mhard-quad-float' - Generate output containing quad-word (long double) floating point - instructions. - -`-msoft-quad-float' - Generate output containing library calls for quad-word (long - double) floating point instructions. The functions called are - those specified in the SPARC ABI. This is the default. - - As of this writing, there are no sparc implementations that have - hardware support for the quad-word floating point instructions. - They all invoke a trap handler for one of these instructions, and - then the trap handler emulates the effect of the instruction. - Because of the trap handler overhead, this is much slower than - calling the ABI library routines. Thus the `-msoft-quad-float' - option is the default. - -`-mno-epilogue' -`-mepilogue' - With `-mepilogue' (the default), the compiler always emits code for - function exit at the end of each function. Any function exit in - the middle of the function (such as a return statement in C) will - generate a jump to the exit code at the end of the function. - - With `-mno-epilogue', the compiler tries to emit exit code inline - at every function exit. - -`-mno-flat' -`-mflat' - With `-mflat', the compiler does not generate save/restore - instructions and will use a "flat" or single register window - calling convention. This model uses %i7 as the frame pointer and - is compatible with the normal register window model. Code from - either may be intermixed. The local registers and the input - registers (0-5) are still treated as "call saved" registers and - will be saved on the stack as necessary. - - With `-mno-flat' (the default), the compiler emits save/restore - instructions (except for leaf functions) and is the normal mode of - operation. - -`-mno-unaligned-doubles' -`-munaligned-doubles' - Assume that doubles have 8 byte alignment. This is the default. - - With `-munaligned-doubles', GNU CC assumes that doubles have 8 byte - alignment only if they are contained in another type, or if they - have an absolute address. Otherwise, it assumes they have 4 byte - alignment. Specifying this option avoids some rare compatibility - problems with code generated by other compilers. It is not the - default because it results in a performance loss, especially for - floating point code. - -`-mv8' -`-msparclite' - These two options select variations on the SPARC architecture. - - By default (unless specifically configured for the Fujitsu - SPARClite), GCC generates code for the v7 variant of the SPARC - architecture. - - `-mv8' will give you SPARC v8 code. The only difference from v7 - code is that the compiler emits the integer multiply and integer - divide instructions which exist in SPARC v8 but not in SPARC v7. - - `-msparclite' will give you SPARClite code. This adds the integer - multiply, integer divide step and scan (`ffs') instructions which - exist in SPARClite but not in SPARC v7. - - These options are deprecated and will be deleted in GNU CC 2.9. - They have been replaced with `-mcpu=xxx'. - -`-mcypress' -`-msupersparc' - These two options select the processor for which the code is - optimised. - - With `-mcypress' (the default), the compiler optimizes code for the - Cypress CY7C602 chip, as used in the SparcStation/SparcServer 3xx - series. This is also appropriate for the older SparcStation 1, 2, - IPX etc. - - With `-msupersparc' the compiler optimizes code for the SuperSparc - cpu, as used in the SparcStation 10, 1000 and 2000 series. This - flag also enables use of the full SPARC v8 instruction set. - - These options are deprecated and will be deleted in GNU CC 2.9. - They have been replaced with `-mcpu=xxx'. - -`-mcpu=CPU_TYPE' - Set architecture type and instruction scheduling parameters for - machine type CPU_TYPE. Supported values for CPU_TYPE are `v7', - `cypress', `v8', `supersparc', `sparclite', `f930', `f934', - `sparclet', `tsc701', `v8plus', `v9', and `ultrasparc'. - -`-mtune=CPU_TYPE' - Set the instruction scheduling parameters for machine type - CPU_TYPE, but do not set the architecture type as the option - `-mcpu='CPU_TYPE would. The same values for `-mcpu='CPU_TYPE are - used for `-mtune='CPU_TYPE. - -`-malign-loops=NUM' - Align loops to a 2 raised to a NUM byte boundary. If - `-malign-loops' is not specified, the default is 2. - -`-malign-jumps=NUM' - Align instructions that are only jumped to to a 2 raised to a NUM - byte boundary. If `-malign-jumps' is not specified, the default - is 2. - -`-malign-functions=NUM' - Align the start of functions to a 2 raised to NUM byte boundary. - If `-malign-functions' is not specified, the default is 2 if - compiling for 32 bit sparc, and 5 if compiling for 64 bit sparc. - - These `-m' switches are supported in addition to the above on the -SPARCLET processor. - -`-mlittle-endian' - Generate code for a processor running in little-endian mode. - -`-mlive-g0' - Treat register `%g0' as a normal register. GCC will continue to - clobber it as necessary but will not assume it always reads as 0. - -`-mbroken-saverestore' - Generate code that does not use non-trivial forms of the `save' and - `restore' instructions. Early versions of the SPARCLET processor - do not correctly handle `save' and `restore' instructions used with - arguments. They correctly handle them used without arguments. A - `save' instruction used without arguments increments the current - window pointer but does not allocate a new stack frame. It is - assumed that the window overflow trap handler will properly handle - this case as will interrupt handlers. - - These `-m' switches are supported in addition to the above on SPARC -V9 processors in 64 bit environments. - -`-mlittle-endian' - Generate code for a processor running in little-endian mode. - -`-m32' -`-m64' - Generate code for a 32 bit or 64 bit environment. The 32 bit - environment sets int, long and pointer to 32 bits. The 64 bit - environment sets int to 32 bits and long and pointer to 64 bits. - -`-mcmodel=medlow' - Generate code for the Medium/Low code model: the program must be - linked in the low 32 bits of the address space. Pointers are 64 - bits. Programs can be statically or dynamically linked. - -`-mcmodel=medmid' - Generate code for the Medium/Middle code model: the program must - be linked in the low 44 bits of the address space, the text - segment must be less than 2G bytes, and data segment must be - within 2G of the text segment. Pointers are 64 bits. - -`-mcmodel=medany' - Generate code for the Medium/Anywhere code model: the program may - be linked anywhere in the address space, the text segment must be - less than 2G bytes, and data segment must be within 2G of the text - segment. Pointers are 64 bits. - -`-mcmodel=embmedany' - Generate code for the Medium/Anywhere code model for embedded - systems: assume a 32 bit text and a 32 bit data segment, both - starting anywhere (determined at link time). Register %g4 points - to the base of the data segment. Pointers still 64 bits. - Programs are statically linked, PIC is not supported. - -`-mstack-bias' -`-mno-stack-bias' - With `-mstack-bias', GNU CC assumes that the stack pointer, and - frame pointer if present, are offset by -2047 which must be added - back when making stack frame references. Otherwise, assume no - such offset is present. - - -File: gcc.info, Node: Convex Options, Next: AMD29K Options, Prev: SPARC Options, Up: Submodel Options - -Convex Options --------------- - - These `-m' options are defined for Convex: - -`-mc1' - Generate output for C1. The code will run on any Convex machine. - The preprocessor symbol `__convex__c1__' is defined. - -`-mc2' - Generate output for C2. Uses instructions not available on C1. - Scheduling and other optimizations are chosen for max performance - on C2. The preprocessor symbol `__convex_c2__' is defined. - -`-mc32' - Generate output for C32xx. Uses instructions not available on C1. - Scheduling and other optimizations are chosen for max performance - on C32. The preprocessor symbol `__convex_c32__' is defined. - -`-mc34' - Generate output for C34xx. Uses instructions not available on C1. - Scheduling and other optimizations are chosen for max performance - on C34. The preprocessor symbol `__convex_c34__' is defined. - -`-mc38' - Generate output for C38xx. Uses instructions not available on C1. - Scheduling and other optimizations are chosen for max performance - on C38. The preprocessor symbol `__convex_c38__' is defined. - -`-margcount' - Generate code which puts an argument count in the word preceding - each argument list. This is compatible with regular CC, and a few - programs may need the argument count word. GDB and other - source-level debuggers do not need it; this info is in the symbol - table. - -`-mnoargcount' - Omit the argument count word. This is the default. - -`-mvolatile-cache' - Allow volatile references to be cached. This is the default. - -`-mvolatile-nocache' - Volatile references bypass the data cache, going all the way to - memory. This is only needed for multi-processor code that does - not use standard synchronization instructions. Making - non-volatile references to volatile locations will not necessarily - work. - -`-mlong32' - Type long is 32 bits, the same as type int. This is the default. - -`-mlong64' - Type long is 64 bits, the same as type long long. This option is - useless, because no library support exists for it. - - -File: gcc.info, Node: AMD29K Options, Next: ARM Options, Prev: Convex Options, Up: Submodel Options - -AMD29K Options --------------- - - These `-m' options are defined for the AMD Am29000: - -`-mdw' - Generate code that assumes the `DW' bit is set, i.e., that byte and - halfword operations are directly supported by the hardware. This - is the default. - -`-mndw' - Generate code that assumes the `DW' bit is not set. - -`-mbw' - Generate code that assumes the system supports byte and halfword - write operations. This is the default. - -`-mnbw' - Generate code that assumes the systems does not support byte and - halfword write operations. `-mnbw' implies `-mndw'. - -`-msmall' - Use a small memory model that assumes that all function addresses - are either within a single 256 KB segment or at an absolute - address of less than 256k. This allows the `call' instruction to - be used instead of a `const', `consth', `calli' sequence. - -`-mnormal' - Use the normal memory model: Generate `call' instructions only when - calling functions in the same file and `calli' instructions - otherwise. This works if each file occupies less than 256 KB but - allows the entire executable to be larger than 256 KB. This is - the default. - -`-mlarge' - Always use `calli' instructions. Specify this option if you expect - a single file to compile into more than 256 KB of code. - -`-m29050' - Generate code for the Am29050. - -`-m29000' - Generate code for the Am29000. This is the default. - -`-mkernel-registers' - Generate references to registers `gr64-gr95' instead of to - registers `gr96-gr127'. This option can be used when compiling - kernel code that wants a set of global registers disjoint from - that used by user-mode code. - - Note that when this option is used, register names in `-f' flags - must use the normal, user-mode, names. - -`-muser-registers' - Use the normal set of global registers, `gr96-gr127'. This is the - default. - -`-mstack-check' -`-mno-stack-check' - Insert (or do not insert) a call to `__msp_check' after each stack - adjustment. This is often used for kernel code. - -`-mstorem-bug' -`-mno-storem-bug' - `-mstorem-bug' handles 29k processors which cannot handle the - separation of a mtsrim insn and a storem instruction (most 29000 - chips to date, but not the 29050). - -`-mno-reuse-arg-regs' -`-mreuse-arg-regs' - `-mno-reuse-arg-regs' tells the compiler to only use incoming - argument registers for copying out arguments. This helps detect - calling a function with fewer arguments than it was declared with. - -`-mno-impure-text' -`-mimpure-text' - `-mimpure-text', used in addition to `-shared', tells the compiler - to not pass `-assert pure-text' to the linker when linking a - shared object. - -`-msoft-float' - Generate output containing library calls for floating point. - *Warning:* the requisite libraries are not part of GNU CC. - Normally the facilities of the machine's usual C compiler are - used, but this can't be done directly in cross-compilation. You - must make your own arrangements to provide suitable library - functions for cross-compilation. - - -File: gcc.info, Node: ARM Options, Next: M32R/D Options, Prev: AMD29K Options, Up: Submodel Options - -ARM Options ------------ - - These `-m' options are defined for Advanced RISC Machines (ARM) -architectures: - -`-mapcs-frame' - Generate a stack frame that is compliant with the ARM Procedure - Call Standard for all functions, even if this is not strictly - necessary for correct execution of the code. - -`-mapcs-26' - Generate code for a processor running with a 26-bit program - counter, and conforming to the function calling standards for the - APCS 26-bit option. This option replaces the `-m2' and `-m3' - options of previous releases of the compiler. - -`-mapcs-32' - Generate code for a processor running with a 32-bit program - counter, and conforming to the function calling standards for the - APCS 32-bit option. This option replaces the `-m6' option of - previous releases of the compiler. - -`-mhard-float' - Generate output containing floating point instructions. This is - the default. - -`-msoft-float' - Generate output containing library calls for floating point. - *Warning:* the requisite libraries are not available for all ARM - targets. Normally the facilities of the machine's usual C - compiler are used, but this cannot be done directly in - cross-compilation. You must make your own arrangements to provide - suitable library functions for cross-compilation. - - `-msoft-float' changes the calling convention in the output file; - therefore, it is only useful if you compile *all* of a program with - this option. In particular, you need to compile `libgcc.a', the - library that comes with GNU CC, with `-msoft-float' in order for - this to work. - -`-mlittle-endian' - Generate code for a processor running in little-endian mode. This - is the default for all standard configurations. - -`-mbig-endian' - Generate code for a processor running in big-endian mode; the - default is to compile code for a little-endian processor. - -`-mwords-little-endian' - This option only applies when generating code for big-endian - processors. Generate code for a little-endian word order but a - big-endian byte order. That is, a byte order of the form - `32107654'. Note: this option should only be used if you require - compatibility with code for big-endian ARM processors generated by - versions of the compiler prior to 2.8. - -`-mshort-load-bytes' - Do not try to load half-words (eg `short's) by loading a word from - an unaligned address. For some targets the MMU is configured to - trap unaligned loads; use this option to generate code that is - safe in these environments. - -`-mno-short-load-bytes' - Use unaligned word loads to load half-words (eg `short's). This - option produces more efficient code, but the MMU is sometimes - configured to trap these instructions. - -`-mbsd' - This option only applies to RISC iX. Emulate the native BSD-mode - compiler. This is the default if `-ansi' is not specified. - -`-mxopen' - This option only applies to RISC iX. Emulate the native - X/Open-mode compiler. - -`-mno-symrename' - This option only applies to RISC iX. Do not run the assembler - post-processor, `symrename', after code has been assembled. - Normally it is necessary to modify some of the standard symbols in - preparation for linking with the RISC iX C library; this option - suppresses this pass. The post-processor is never run when the - compiler is built for cross-compilation. - - -File: gcc.info, Node: M32R/D Options, Next: M88K Options, Prev: ARM Options, Up: Submodel Options - -M32R/D Options --------------- - - These `-m' options are defined for Mitsubishi M32R/D architectures: - -`-mcode-model=small' - Assume all objects live in the lower 16MB of memory (so that their - addresses can be loaded with the `ld24' instruction), and assume - all subroutines are reachable with the `bl' instruction. This is - the default. - - The addressability of a particular object can be set with the - `model' attribute. - -`-mcode-model=medium' - Assume objects may be anywhere in the 32 bit address space (the - compiler will generate `seth/add3' instructions to load their - addresses), and assume all subroutines are reachable with the `bl' - instruction. - -`-mcode-model=large' - Assume objects may be anywhere in the 32 bit address space (the - compiler will generate `seth/add3' instructions to load their - addresses), and assume subroutines may not be reachable with the - `bl' instruction (the compiler will generate the much slower - `seth/add3/jl' instruction sequence). - -`-msdata=none' - Disable use of the small data area. Variables will be put into - one of `.data', `bss', or `.rodata' (unless the `section' - attribute has been specified). This is the default. - - The small data area consists of sections `.sdata' and `.sbss'. - Objects may be explicitly put in the small data area with the - `section' attribute using one of these sections. - -`-msdata=sdata' - Put small global and static data in the small data area, but do not - generate special code to reference them. - -`-msdata=use' - Put small global and static data in the small data area, and - generate special instructions to reference them. - -`-G NUM' - Put global and static objects less than or equal to NUM bytes into - the small data or bss sections instead of the normal data or bss - sections. The default value of NUM is 8. The `-msdata' option - must be set to one of `sdata' or `use' for this option to have any - effect. - - All modules should be compiled with the same `-G NUM' value. - Compiling with different values of NUM may or may not work; if it - doesn't the linker will give an error message - incorrect code - will not be generated. - |