OpenLibm/src/cdefs-compat.h
Alex Arslan 72bfab46a0
Avoid redefining macros defined by the system
In particular, OpenBSD already defines __GNUC_PREREQ__, __BEGIN_DECLS,
and __warn_references. Hiding the definitions behind #ifndef guards
avoids warnings when building.
2018-04-06 14:41:06 -07:00

82 lines
2.3 KiB
C

#ifndef _CDEFS_COMPAT_H_
#define _CDEFS_COMPAT_H_
#if !defined(__BEGIN_DECLS)
#if defined(__cplusplus)
#define __BEGIN_DECLS extern "C" {
#define __END_DECLS }
#else
#define __BEGIN_DECLS
#define __END_DECLS
#endif
#endif /* !defined(__BEGIN_DECLS) */
#ifdef __GNUC__
#ifndef __strong_reference
#ifdef __APPLE__
#define __strong_reference(sym,aliassym) __weak_reference(sym,aliassym)
#else
#define __strong_reference(sym,aliassym) \
OLM_DLLEXPORT extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)));
#endif /* __APPLE__ */
#endif /* __strong_reference */
#ifndef __weak_reference
#ifdef __ELF__
#ifdef __STDC__
#define __weak_reference(sym,alias) \
__asm__(".weak " #alias); \
__asm__(".equ " #alias ", " #sym)
#ifndef __warn_references
#define __warn_references(sym,msg) \
__asm__(".section .gnu.warning." #sym); \
__asm__(".asciz \"" msg "\""); \
__asm__(".previous")
#endif /* __warn_references */
#else
#define __weak_reference(sym,alias) \
__asm__(".weak alias"); \
__asm__(".equ alias, sym")
#ifndef __warn_references
#define __warn_references(sym,msg) \
__asm__(".section .gnu.warning.sym"); \
__asm__(".asciz \"msg\""); \
__asm__(".previous")
#endif /* __warn_references */
#endif /* __STDC__ */
#elif defined(__clang__) /* CLANG */
#ifdef __STDC__
#define __weak_reference(sym,alias) \
__asm__(".weak_reference " #alias); \
__asm__(".set " #alias ", " #sym)
#else
#define __weak_reference(sym,alias) \
__asm__(".weak_reference alias");\
__asm__(".set alias, sym")
#endif
#else /* !__ELF__ */
#ifdef __STDC__
#define __weak_reference(sym,alias) \
__asm__(".stabs \"_" #alias "\",11,0,0,0"); \
__asm__(".stabs \"_" #sym "\",1,0,0,0")
#ifndef __warn_references
#define __warn_references(sym,msg) \
__asm__(".stabs \"" msg "\",30,0,0,0"); \
__asm__(".stabs \"_" #sym "\",1,0,0,0")
#endif /* __warn_references */
#else
#define __weak_reference(sym,alias) \
__asm__(".stabs \"_/**/alias\",11,0,0,0"); \
__asm__(".stabs \"_/**/sym\",1,0,0,0")
#ifndef __warn_references
#define __warn_references(sym,msg) \
__asm__(".stabs msg,30,0,0,0"); \
__asm__(".stabs \"_/**/sym\",1,0,0,0")
#endif /* __warn_references */
#endif /* __STDC__ */
#endif /* __ELF__ */
#endif /* __weak_reference */
#endif /* __GNUC__ */
#endif /* _CDEFS_COMPAT_H_ */