compiler building blocks: definitions for all musl-libc ELF targets.

+ cbb-musl-elf.h: this header provides the compiler with necessary
  knowledge about the target system libc (musl), covering libc
  features, preferences, and link information (specs).

+ following the naming convention of musl's dynamic linker, this
  header requires CBB_ARCH to be defined.

signed-off by Z. Gilboa; see copying.midipix (9cd0746c) for additional information.

1 files changed, 114 insertions, 0 deletions

diff --git a/libc/cbb-musl-elf.h b/libc/cbb-musl-elf.h
new file mode 100644
index 000000000..6c345bb99
--- /dev/null
+++ b/libc/cbb-musl-elf.h
@@ -0,0 +1,114 @@
+/*************************************************************************/
+/*  compiler building blocks: definitions for all musl-libc ELF targets  */
+/*************************************************************************/
+
+#ifndef __ASSEMBLER__
+
+#include "cbb-common.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* features */
+#undef	TARGET_C99_FUNCTIONS
+#define	TARGET_C99_FUNCTIONS	(1)
+
+#undef  TARGET_HAS_SINCOS
+#define TARGET_HAS_SINCOS	(0)
+
+#undef  TARGET_POSIX_IO
+#define TARGET_POSIX_IO		(1)
+
+
+/* preferences */
+#undef  NO_IMPLICIT_EXTERN_C
+#define NO_IMPLICIT_EXTERN_C	(1)
+
+#undef  GTHREAD_USE_WEAK
+#define GTHREAD_USE_WEAK	(0)
+
+#undef  USE_PT_GNU_EH_FRAME
+#define USE_PT_GNU_EH_FRAME	(1)
+
+#undef  STANDARD_INCLUDE_DIR
+#define STANDARD_INCLUDE_DIR	"/include"
+
+#undef  LOCAL_INCLUDE_DIR
+#define LOCAL_INCLUDE_DIR	"/local/include"
+
+
+/* arch */
+#define CBB_STR(s)		#s
+#define CBB_XSTR(s)		CBB_STR(s)
+
+#undef  MUSL_DYNAMIC_LINKER
+#define MUSL_DYNAMIC_LINKER	"ld-musl-" CBB_XSTR(CBB_ARCH) ".so.1"
+
+#ifndef CBB_LINK_EMULATION
+#define CBB_LINK_EMULATION	""
+#endif
+
+#undef  LINK_EMULATION
+#define LINK_EMULATION		CBB_LINK_EMULATION
+
+
+/* specs */
+#undef  CC1_SPEC
+#define CC1_SPEC		"%(cc1_cpu) %{profile:-p}"
+
+#undef  CPP_SPEC
+#define CPP_SPEC		"%{posix:-D_POSIX_SOURCE}"
+
+#undef  STARTFILE_PREFIX_SPEC
+#define STARTFILE_PREFIX_SPEC	"%R/lib/"
+
+#undef  LINK_EH_SPEC
+#define LINK_EH_SPEC		" --eh-frame-hdr "
+
+#undef  LINK_GCC_C_SEQUENCE_SPEC
+#define LINK_GCC_C_SEQUENCE_SPEC						   \
+				"%{static:--start-group} "			   \
+				"%L %G "					   \
+				"%{static:--end-group}%{!static:%G} "		   \
+				"--as-needed -lc"
+
+#undef  LIB_SPEC
+#define LIB_SPEC		"%{pthread:-lpthread} "				   \
+				"%{shared:-lc} "
+
+#undef  STARTFILE_SPEC
+#define STARTFILE_SPEC		"%{!shared: "					   \
+					"%(startfile_prefix_spec)%{pie:S}crt1.o} " \
+					"%(startfile_prefix_spec)crti.o "	   \
+				"%{shared|pie:"					   \
+					"crtbeginS.o%s;:crtbegin.o%s}"
+
+#undef  ENDFILE_SPEC
+#define ENDFILE_SPEC		"%{shared|pie:crtendS.o%s;:crtend.o%s} "	   \
+				"%(startfile_prefix_spec)crtn.o"
+
+
+#undef  LINK_EMULATION_SPEC
+#define LINK_EMULATION_SPEC	{ "link_emulation", LINK_EMULATION }
+
+#undef  DYNAMIC_LINKER_SPEC
+#define DYNAMIC_LINKER_SPEC	{ "dynamic_linker", \
+				  "%(startfile_prefix_spec)" MUSL_DYNAMIC_LINKER }
+
+#undef  SUBTARGET_EXTRA_SPECS
+#define SUBTARGET_EXTRA_SPECS	LINK_EMULATION_SPEC , DYNAMIC_LINKER_SPEC
+
+#undef  LINK_SPEC
+#define LINK_SPEC		"-dynamic-linker %(dynamic_linker) "		   \
+				"%{shared:-shared} "				   \
+				"%{static:-static} "				   \
+				"%{rdynamic:-export-dynamic}"
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __ASSEMBLER__ */