| Feeble attempt to document the horde of #defines we deal with. |
| Editors, please make your descriptions short but informative. |
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| __BEGIN_DECLS, __END_DECLS |
| Defined to either empty or 'extern "C" {' and '}' if included by C++. |
| |
| __USE_GNU, __USE_BSD, __USE_XOPEN[2K], __USE_SVID, __USE_POSIX... |
| If defined, user program which included us requests compat additions |
| from relevant standard or Unix flavor. See features.h for full list. |
| |
| __USE_FILE_OFFSET64 |
| __USE_LARGEFILE[64] |
| _LARGEFILE[64]_SOURCE |
| _FILE_OFFSET_BITS |
| ??? |
| |
| __THROW |
| Function annotation "I do not throw anything". |
| __NTH(func(params)) |
| Function annotation "I do not throw anything". |
| Needed for situatuons when it's unclear on what side of "func(params)" |
| the "throw()" or "attribute((nothrow))" should eventually appear. |
| Messy, eh? |
| |
| return_type __REDIRECT(name, (params), alias) |
| declare alias to "name(params)" |
| return_type __REDIRECT_NTH(name, (params), alias) |
| declare alias to "name(params) __THROW" |
| |
| __BIG_ENDIAN 4321 |
| __LITTLE_ENDIAN 1234 |
| Should be always as shown. __PDP_ENDIAN is historic, ignore? |
| __BYTE_ORDER, __FLOAT_WORD_ORDER |
| Should be defined to __BIG_ENDIAN or __LITTLE_ENDIAN. |
| Usage: "#if __BYTE_ORDER == __LITTLE_ENDIAN ..." |
| __USE_BSD adds versions without leading "__" for above four defines. |
| _BIG_ENDIAN, __BIG_ENDIAN__ |
| _LITTLE_ENDIAN, __LITTLE_ENDIAN__ |
| Defined (to what?) by gcc for some architectures to indicate endianness. |
| Seems that the fact of defined-ness is an indicator, not the value. |
| |
| __USE_EXTERN_INLINES |
| If defined, headers will supply some function as inlines. |
| uclibc itself is built with this option off and provides |
| out-of-line version of every inlined function in case user program |
| calls it instead of using an inline. |
| _EXTERN_INLINE |
| If not defined by user prior to #include, will be defined to |
| "extern inline" or equivalent. IOW, if user defines it prior |
| #include, it replaces "extern __inline" string in inline definitions |
| (those enabled by __USE_EXTERN_INLINES) with something else. |
| A few uclibc .c files use it to create non-inlined functions |
| by defining it to "". |
| __extern_inline |
| Defined to "extern inline", modulo gcc/C standard deviations. |
| Can't be used by user to play tricks as with _EXTERN_INLINE. |
| |
| internal_function |
| Used to modify function's calling convention, if "standard" one |
| is suboptimal. Examples: |
| int func(params) internal_function; |
| int internal_function func(params) { body } |
| |
| _LIBC |
| Defined only at libc build time. It is physically deleted |
| from the headers (using unifdef tool) in installed headers ("make install"). |
| |
| __UCLIBC_XXX |
| uclibc-internal and uclibc-specific defines. In particular: |
| __UCLIBC_HAS_XXX__, __UCLIBC_HAVE_XXX__ |
| __UCLIBC_HAS_XXX__ are booleans (defined/undefined), defined in |
| uClibc_config.h and generated from uclibc .config file. |
| __UCLIBC_HAVE_XXX__ are booleans from bits/uClibc_arch_features.h |
| (there are more __UCLIBC_XXX defines there) |
| |
| _IEEE_LIBM |
| Always defined at libm build time |
| __LDBL_COMPAT |
| Never defined, TODO: remove? |
| |
| __SSP_ALL__ |
| All functions, even small ones, have stack smashing protection |
| prologue enabled. |