--- name: "bcc" section: "1" platform: "linux" package: "bcc" version: "0.16.21-2" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/bcc" --- # bcc(1) Bruce's C compiler ## NAME bcc - Bruce's C compiler ## SYNOPSIS **bcc** \[**-03EGNOPSVcegvwxW**\] \[**-Aas\_option**\] \[**-Bexecutable\_prefix**\] \[**-Ddefine**\] \[**-Uundef**\] \[**-Mc\_mode**\] \[**-o outfile**\] \[**-ansi**\] \[**-Ccc1\_option**\] \[**-Pcpp\_option**\] \[**-Iinclude\_dir**\] \[**-Lld\_option**\] \[**-Ttmpdir**\] \[**-Qc386\_option**\] \[**-ttext\_segno**\] \[**ld\_options**\] \[**infiles**\] ## DESCRIPTION **Bcc** is a simple C compiler that produces 8086 assembler, in addition compiler compile time options allow 80386 or 6809 versions. The compiler understands traditional K&R C with just the restriction that bit fields are mapped to one of the other integer types. The default operation is to produce an 8086 executable called **a.out** from the source file. ## OPTIONS - **-ansi** Pass the C source through **unprotoize** after preprocessing and before code generation. This will allow *some* ansi C to be compiled but it is definitely **NOT** a true ansi-C compiler. - **-0** 8086 target (works on 80386 host, but not 6809) - **-3** 80386 target (may work on 8086 host, but not 6809) - **-A** pass remainder of option to assembler (e.g. -A-l -Alistfile for a listing) - **-B** prefix for executable search path (as usual; the search order is all paths specified using **-B**, in order, then the path given in the environment variable **BCC\_EXEC\_PREFIX** if that is set, then the compiled-in defaults (something like /usr/lib/bcc/ followed by /usr/bin/) - **-C** pass remainder of option to bcc-cc1, see code generation options. - **-D** preprocessor define - **-E** produce preprocessor output to standard out. - **-G** produce GCC objects (Same as -Mg) - **-Ixyz** include search 'xyz' path - **-I** don't add default include to search list - **-Lxyz** add directory name 'xyz' to the head of the list of library directories searched - **-L** don't add default library to search list - **-Md** alters the arguments for all passes to produce MSDOS executable COM files. These are small model executables, use **-i** to get tiny model. - **-Mf** sets bcc to pass the **-c** and **-f** arguments to the code generator for smaller faster code. Note this code is not compatible with the standard calling conventions so a different version of the C library is linked too. - **-Mc** sets bcc to pass the **-c** argument to the code generator for smaller faster code. Note the standard libc is normally transparent to this, but there are exceptions. - **-Ms** alters the arguments for all passes and selects C-library to produce standalone Linux-86 executables - **-Ml** switches to i386-Linux code generator and library. This configuration accepts the **-z** flag to generate QMAGIC a.out files instead of the normal OMAGIC. - **-Mg** switches to i386-Linux code generator and generates OMAGIC object files that can be linked with some versions of gcc; unfortunately the most recent versions use 'collect2' to link and this crashes. - **-N** makes the linker produce a native a.out file (Linux OMAGIC) if combined with -3 the executable will run under Linux-i386. - **-O** optimize, call **copt**(**1**) to optimize 8086 code. Specifiers to choose which rules **copt** should use can be appended to the **-O** and the option can be repeated. - **-P** produce preprocessor output with no line numbers to standard output. - **-Q** pass full option to c386 (Only for c386 version) - **-S** produce assembler file - **-T** temporary directory (overrides previous value and default; default is from the environment variable TMPDIR if that is set, otherwise /tmp) - **-U** preprocessor undefine - **-V** print names of files being compiled - **-X** pass remainder of option to linker (e.g. -X-Ofile is passed to the linker as -Ofile) - **-c** produce object file - **-f** turn on floating point support, no effect with i386, changes libc library with 8086 code. - **-g** produce debugging info (ignored.) - **-o** output file name follows (assembler, object or executable) (as usual) - **-p** produce profiling info (ignored.) - **-t1** pass to the assembler to renumber the text segment for multi-segment programs. - **-v** print names and args of subprocesses being run. Two or more -v's print names of files being unlinked. Three or more -v's print names of paths being searched. - **-w** Suppress any warning diagnostics. - **-W** Turn **on** assembler warning messages. - **-x** don't include crt0.o in the link. - **-i** don't pass **-i** to the linker so that it will create an impure executable. - **-7** Turn on ancient C mode (see CODE GENERATOR OPTIONS below). Among other things, this disables valuable error checks and even parses certain constructs incompatibly (e.g. *=-* is postdecrement instead of an assignment of a negative number) to later C standards, so this option should only be used with ancient code. To generate executables for a V7 variant you should tell linker to generate old a.out header with **-X-7** option. Other options are passed to the linker, in particular -lx, -M, -m, -s, -H. ## CODE GENERATOR OPTIONS These are all options that the code generator pass **bcc-cc1** understands, only some will be useful for the **-C** option of bcc. - **-0** 8086 target (works even on 80386 host, not on 6809) - **-3** 80386 target (may work even on 8086 host, not on 6809) - **-D** define (as usual) - **-E** produce preprocessor output (as usual) - **-I** include search path (as usual) - **-P** produce preprocessor output with no line numbers (as usual) - **-c** produce code with caller saving regs before function calls - **-d** print debugging information in assembly output - **-f** produce code with 1st argument passed in a register (AX, EAX or X) - **-l** produce code for 2 3 1 0 long byte order (only works in 16-bit code), a special library of compiler helper functions is needed for this mode. - **-o** assembler output file name follows - **-p** produce (almost) position-independent code (only for the 6809) - **-t** print source code in assembly output - **-w** print what cc1 thinks is the location counter in assembly output - **-7** Accept various obsolete construct for ancient C compilers, including Ritchie's Sixth Edition UNIX C compiler and Seventh Edition UNIX Portable C compiler. Enough of these compilers is emulated to compile all of Seventh Edition userspace and kernel. All the options except -D, -I and -o may be turned off by following the option letter by a '-'. Options are processed left to right so the last setting has precedence. ## PREPROCESSOR DEFINES The preprocessor has a number of manifest constants. - **\_\_BCC\_\_ 1** The compiler identifier, normally used to avoid compiler limitations. - **\_\_FILE\_\_** stringized name of current input file - **\_\_LINE\_\_** current line number - **\_\_MSDOS\_\_ 1** compiler is configured for generating MSDOS executable COM files. - **\_\_STANDALONE\_\_ 1** compiler is configured for generating standalone executables. - **\_\_AS386\_16\_\_ 1** compiler is generating 16 bit 8086 assembler and the **#asm** keyword is available for including 8086 code. - **\_\_AS386\_32\_\_ 1** compiler is generating 32 bit 80386 assembler and the **#asm** keyword is available for including 80386 code. - **\_\_CALLER\_SAVES\_\_ 1** compiler calling conventions are altered so the calling function must save the *SI* and *DI* registers if they are in use (ESI and EDI on the 80386) - **\_\_FIRST\_ARG\_IN\_AX\_\_ 1** compiler calling conventions are altered so the calling function is passing the first argument to the function in the *AX* (or *EAX*) register. - **\_\_LONG\_BIG\_ENDIAN\_\_ 1** alters the word order of code generated by the 8086 compiler. These defines only occur in the 6809 version of the compiler. - **\_\_AS09\_\_ 1** compiler is generating 6809 code - **\_\_FIRST\_ARG\_IN\_X\_\_ 1** the first argument to functions is passed in the *X* register. - **\_\_POS\_INDEPENDENT\_\_ 1** the code generated is (almost) position independent. ## ENVIRONMENT - **BCC\_EXEC\_PREFIX** default directory to search for compiler passes - **TMPDIR** directory to place temporary files (default /tmp) ## DIRECTORIES All the include, library and compiler components are stored under the */usr/lib/bcc* directory under Linux-i386, this is laid out the same as a */usr* filesystem and if bcc is to be the primary compiler on a system it should be moved there. The configuration for this is in the **bcc.c** source file only, all other executables are independent of location. The library installation also creates the file **/usr/lib/liberror.txt**, this path is hardcoded into the C library. The **bcc** executable itself, **as86** and **ld86** are in /usr/bin. ## SEE ALSO [**as86**(1)](/as86/1.md), [**ld86**(1)](/ld86/1.md), [**elksemu**(1)](/elksemu/1.md) ## BUGS The bcc.c compiler driver source is very untidy. The linker, ld86, produces a broken a.out object file if given one input and the **-r** option this is so it is compatible with pre-dev86 versions. ## AUTHOR **bcc** was written by Bruce Evans.