I assume you're using a gnuc compiler (or one derived from it). If so you should be able to get the list of pre-defines provided by the compiler with the following command:
echo . | g++ -dM -E -
Add whatever extra compiler arguments you use to target your specific platform.
Show me the output from that command and I can help you try to identify what might be wrong in the as_config.h file for your compiler and platform.
These are all the flags used: CXXFLAGS='-O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -m64 -fno-strict-aliasing'
This is the output of the command:
#define __DBL_MIN_EXP__ (-1021)
#define __builtin_vsx_xvmsubmsp __builtin_vsx_xvmsubsp
#define __UINT_LEAST16_MAX__ 0xffff
#define __ATOMIC_ACQUIRE 2
#define __FLT_MIN__ 1.17549435082228750796873653722225e-38F
#define __GCC_IEC_559_COMPLEX 2
#define __UINT_LEAST8_TYPE__ unsigned char
#define __INTMAX_C(c) c ## L
#define __CHAR_BIT__ 8
#define _ARCH_PPCGR 1
#define __UINT8_MAX__ 0xff
#define __builtin_vsx_xvnmaddadp __builtin_vsx_xvnmadddp
#define __WINT_MAX__ 0xffffffffU
#define __PPC64__ 1
#define __RECIPF__ 1
#define __builtin_vsx_xxlnor __builtin_vec_nor
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __SIZE_MAX__ 0xffffffffffffffffUL
#define __WCHAR_MAX__ 0x7fffffff
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
#define __DBL_DENORM_MIN__ ((double)4.94065645841246544176568792868221e-324L)
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
#define __GCC_ATOMIC_CHAR_LOCK_FREE 2
#define __GCC_IEC_559 2
#define __FLT_EVAL_METHOD__ 0
#define __unix__ 1
#define __GCC_ATOMIC_CHAR32_T_LOCK_FREE 2
#define pixel pixel
#define _ARCH_PPCSQ 1
#define bool bool
#define __UINT_FAST64_MAX__ 0xffffffffffffffffUL
#define __SIG_ATOMIC_TYPE__ int
#define __DBL_MIN_10_EXP__ (-307)
#define __FINITE_MATH_ONLY__ 0
#define __GNUC_PATCHLEVEL__ 1
#define __builtin_vsx_xvnmaddasp __builtin_vsx_xvnmaddsp
#define __UINT_FAST8_MAX__ 0xff
#define __has_include(STR) __has_include__(STR)
#define __DEC64_MAX_EXP__ 385
#define __INT8_C(c) c
#define __builtin_vsx_xvnmsubmdp __builtin_vsx_xvnmsubdp
#define __UINT_LEAST64_MAX__ 0xffffffffffffffffUL
#define __SHRT_MAX__ 0x7fff
#define __LDBL_MAX__ 1.79769313486231580793728971405301e+308L
#define __UINT_LEAST8_MAX__ 0xff
#define __GCC_ATOMIC_BOOL_LOCK_FREE 2
#define _ARCH_PPC 1
#define __UINTMAX_TYPE__ long unsigned int
#define __linux 1
#define __DEC32_EPSILON__ 1E-6DF
#define __CHAR_UNSIGNED__ 1
#define __UINT32_MAX__ 0xffffffffU
#define __LDBL_MAX_EXP__ 1024
#define __WINT_MIN__ 0U
#define __builtin_vsx_xvmaddmdp __builtin_vsx_xvmadddp
#define __linux__ 1
#define __builtin_vsx_vperm __builtin_vec_perm
#define __SCHAR_MAX__ 0x7f
#define __WCHAR_MIN__ (-__WCHAR_MAX__ - 1)
#define vector vector
#define __builtin_vsx_xvnmsubmsp __builtin_vsx_xvnmsubsp
#define __INT64_C(c) c ## L
#define __DBL_DIG__ 15
#define __GCC_ATOMIC_POINTER_LOCK_FREE 2
#define __SIZEOF_INT__ 4
#define __SIZEOF_POINTER__ 8
#define __USER_LABEL_PREFIX__
#define __STDC_HOSTED__ 1
#define __LDBL_HAS_INFINITY__ 1
#define _ARCH_PWR4 1
#define __builtin_vsx_xvmaddmsp __builtin_vsx_xvmaddsp
#define __CMODEL_MEDIUM__ 1
#define __FLT_EPSILON__ 1.19209289550781250000000000000000e-7F
#define __LDBL_MIN__ 2.00416836000897277799610805135016e-292L
#define __STDC_UTF_16__ 1
#define __DEC32_MAX__ 9.999999E96DF
#define __INT32_MAX__ 0x7fffffff
#define __SIZEOF_LONG__ 8
#define __STDC_IEC_559__ 1
#define __STDC_ISO_10646__ 201304L
#define __UINT16_C(c) c
#define __DECIMAL_DIG__ 33
#define __gnu_linux__ 1
#define __has_include_next(STR) __has_include_next__(STR)
#define __LDBL_HAS_QUIET_NAN__ 1
#define _CALL_LINUX 1
#define __GNUC__ 5
#define __FLT_HAS_DENORM__ 1
#define __SIZEOF_LONG_DOUBLE__ 16
#define __powerpc64__ 1
#define __BIGGEST_ALIGNMENT__ 16
#define __DBL_MAX__ ((double)1.79769313486231570814527423731704e+308L)
#define __INT_FAST32_MAX__ 0x7fffffffffffffffL
#define __DBL_HAS_INFINITY__ 1
#define __builtin_vsx_xvnmaddmdp __builtin_vsx_xvnmadddp
#define __DEC32_MIN_EXP__ (-94)
#define __builtin_vsx_xxlandc __builtin_vec_andc
#define __INT_FAST16_TYPE__ long int
#define __LDBL_HAS_DENORM__ 1
#define __DEC128_MAX__ 9.999999999999999999999999999999999E6144DL
#define __INT_LEAST32_MAX__ 0x7fffffff
#define __DEC32_MIN__ 1E-95DF
#define __DBL_MAX_EXP__ 1024
#define __DEC128_EPSILON__ 1E-33DL
#define __PTRDIFF_MAX__ 0x7fffffffffffffffL
#define __STDC_NO_THREADS__ 1
#define __STRUCT_PARM_ALIGN__ 16
#define __LONG_LONG_MAX__ 0x7fffffffffffffffLL
#define __SIZEOF_SIZE_T__ 8
#define __builtin_vsx_xvnmaddmsp __builtin_vsx_xvnmaddsp
#define __PPC__ 1
#define __SIZEOF_WINT_T__ 4
#define __GXX_ABI_VERSION 1008
#define __FLT_MIN_EXP__ (-125)
#define __INT_FAST64_TYPE__ long int
#define __FP_FAST_FMAF 1
#define __DBL_MIN__ ((double)2.22507385850720138309023271733240e-308L)
#define __LONGDOUBLE128 1
#define __LP64__ 1
#define __DEC128_MIN__ 1E-6143DL
#define __REGISTER_PREFIX__
#define __UINT16_MAX__ 0xffff
#define __DBL_HAS_DENORM__ 1
#define __builtin_vsx_xxland __builtin_vec_and
#define __UINT8_TYPE__ unsigned char
#define __NO_INLINE__ 1
#define __FLT_MANT_DIG__ 24
#define __VERSION__ "5.1.1 20150618 (Red Hat 5.1.1-4)"
#define __UINT64_C(c) c ## UL
#define _STDC_PREDEF_H 1
#define __BIG_ENDIAN__ 1
#define __GCC_ATOMIC_INT_LOCK_FREE 2
#define __pixel __attribute__((altivec(pixel__))) unsigned short
#define __FLOAT_WORD_ORDER__ __ORDER_BIG_ENDIAN__
#define __STDC_IEC_559_COMPLEX__ 1
#define __INT32_C(c) c
#define __DEC64_EPSILON__ 1E-15DD
#define __ORDER_PDP_ENDIAN__ 3412
#define __DEC128_MIN_EXP__ (-6142)
#define __INT_FAST32_TYPE__ long int
#define __powerpc__ 1
#define __UINT_LEAST16_TYPE__ short unsigned int
#define unix 1
#define __INT16_MAX__ 0x7fff
#define __SIZE_TYPE__ long unsigned int
#define __UINT64_MAX__ 0xffffffffffffffffUL
#define __INT8_TYPE__ signed char
#define __ELF__ 1
#define __HAVE_BSWAP__ 1
#define __FLT_RADIX__ 2
#define __INT_LEAST16_TYPE__ short int
#define __LDBL_EPSILON__ 4.94065645841246544176568792868221e-324L
#define __UINTMAX_C(c) c ## UL
#define __GNUC_RH_RELEASE__ 4
#define __SIG_ATOMIC_MAX__ 0x7fffffff
#define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2
#define __SIZEOF_PTRDIFF_T__ 8
#define __DEC32_SUBNORMAL_MIN__ 0.000001E-95DF
#define __INT_FAST16_MAX__ 0x7fffffffffffffffL
#define __vector __attribute__((altivec(vector__)))
#define __UINT_FAST32_MAX__ 0xffffffffffffffffUL
#define __UINT_LEAST64_TYPE__ long unsigned int
#define __builtin_vsx_xvmsubadp __builtin_vsx_xvmsubdp
#define __builtin_vsx_xxsel __builtin_vec_sel
#define __FLT_HAS_QUIET_NAN__ 1
#define __bool __attribute__((altivec(bool__))) unsigned
#define __FLT_MAX_10_EXP__ 38
#define __LONG_MAX__ 0x7fffffffffffffffL
#define __DEC128_SUBNORMAL_MIN__ 0.000000000000000000000000000000001E-6143DL
#define __FLT_HAS_INFINITY__ 1
#define __unix 1
#define __UINT_FAST16_TYPE__ long unsigned int
#define __DEC64_MAX__ 9.999999999999999E384DD
#define __CHAR16_TYPE__ short unsigned int
#define __PRAGMA_REDEFINE_EXTNAME 1
#define __INT_LEAST16_MAX__ 0x7fff
#define __DEC64_MANT_DIG__ 16
#define __INT64_MAX__ 0x7fffffffffffffffL
#define __UINT_LEAST32_MAX__ 0xffffffffU
#define __GCC_ATOMIC_LONG_LOCK_FREE 2
#define __INT_LEAST64_TYPE__ long int
#define __INT16_TYPE__ short int
#define __INT_LEAST8_TYPE__ signed char
#define __STDC_VERSION__ 201112L
#define __DEC32_MAX_EXP__ 97
#define _BIG_ENDIAN 1
#define __INT_FAST8_MAX__ 0x7f
#define __INTPTR_MAX__ 0x7fffffffffffffffL
#define linux 1
#define __builtin_vsx_xvmsubasp __builtin_vsx_xvmsubsp
#define __LDBL_MANT_DIG__ 106
#define __DBL_HAS_QUIET_NAN__ 1
#define __SIG_ATOMIC_MIN__ (-__SIG_ATOMIC_MAX__ - 1)
#define __INTPTR_TYPE__ long int
#define __UINT16_TYPE__ short unsigned int
#define __WCHAR_TYPE__ int
#define __SIZEOF_FLOAT__ 4
#define __UINTPTR_MAX__ 0xffffffffffffffffUL
#define __DEC64_MIN_EXP__ (-382)
#define __INT_FAST64_MAX__ 0x7fffffffffffffffL
#define __GCC_ATOMIC_TEST_AND_SET_TRUEVAL 1
#define __RSQRTE__ 1
#define __FLT_DIG__ 6
#define __UINT_FAST64_TYPE__ long unsigned int
#define __INT_MAX__ 0x7fffffff
#define __LONG_DOUBLE_128__ 1
#define __INT64_TYPE__ long int
#define __FLT_MAX_EXP__ 128
#define __builtin_vsx_xxlor __builtin_vec_or
#define __ORDER_BIG_ENDIAN__ 4321
#define __DBL_MANT_DIG__ 53
#define __INT_LEAST64_MAX__ 0x7fffffffffffffffL
#define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2
#define __builtin_vsx_xxlxor __builtin_vec_xor
#define __DEC64_MIN__ 1E-383DD
#define __WINT_TYPE__ unsigned int
#define __UINT_LEAST32_TYPE__ unsigned int
#define __SIZEOF_SHORT__ 2
#define __LDBL_MIN_EXP__ (-968)
#define __INT_LEAST8_MAX__ 0x7f
#define __SIZEOF_INT128__ 16
#define __LDBL_MAX_10_EXP__ 308
#define __ATOMIC_RELAXED 0
#define __DBL_EPSILON__ ((double)2.22044604925031308084726333618164e-16L)
#define _LP64 1
#define __UINT8_C(c) c
#define __INT_LEAST32_TYPE__ int
#define __SIZEOF_WCHAR_T__ 4
#define __UINT64_TYPE__ long unsigned int
#define __builtin_vsx_xvnmsubadp __builtin_vsx_xvnmsubdp
#define __INT_FAST8_TYPE__ signed char
#define __GNUC_STDC_INLINE__ 1
#define __DBL_DECIMAL_DIG__ 17
#define __STDC_UTF_32__ 1
#define __DEC_EVAL_METHOD__ 2
#define __VEC_ELEMENT_REG_ORDER__ __ORDER_BIG_ENDIAN__
#define __builtin_vsx_xvmaddadp __builtin_vsx_xvmadddp
#define __UINT32_C(c) c ## U
#define __INTMAX_MAX__ 0x7fffffffffffffffL
#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
#define __FLT_DENORM_MIN__ 1.40129846432481707092372958328992e-45F
#define _CALL_AIX 1
#define __builtin_vsx_xvnmsubasp __builtin_vsx_xvnmsubsp
#define __INT8_MAX__ 0x7f
#define __UINT_FAST32_TYPE__ long unsigned int
#define __CHAR32_TYPE__ unsigned int
#define __FLT_MAX__ 3.40282346638528859811704183484517e+38F
#define __FP_FAST_FMA 1
#define __INT32_TYPE__ int
#define __SIZEOF_DOUBLE__ 8
#define __FLT_MIN_10_EXP__ (-37)
#define _CALL_AIXDESC 1
#define __INTMAX_TYPE__ long int
#define __DEC128_MAX_EXP__ 6145
#define __ATOMIC_CONSUME 1
#define __GNUC_MINOR__ 1
#define __UINTMAX_MAX__ 0xffffffffffffffffUL
#define __DEC32_MANT_DIG__ 7
#define __builtin_vsx_xvmaddasp __builtin_vsx_xvmaddsp
#define __DBL_MAX_10_EXP__ 308
#define __LDBL_DENORM_MIN__ 4.94065645841246544176568792868221e-324L
#define __INT16_C(c) c
#define __STDC__ 1
#define __builtin_vsx_xvmsubmdp __builtin_vsx_xvmsubdp
#define __PTRDIFF_TYPE__ long int
#define __ATOMIC_SEQ_CST 5
#define __UINT32_TYPE__ unsigned int
#define __UINTPTR_TYPE__ long unsigned int
#define __DEC64_SUBNORMAL_MIN__ 0.000000000000001E-383DD
#define _ARCH_PPC64 1
#define __DEC128_MANT_DIG__ 34
#define __LDBL_MIN_10_EXP__ (-291)
#define __SIZEOF_LONG_LONG__ 8
#define _Bool _Bool
#define __GCC_ATOMIC_LLONG_LOCK_FREE 2
#define __LDBL_DIG__ 31
#define __FLT_DECIMAL_DIG__ 9
#define __UINT_FAST16_MAX__ 0xffffffffffffffffUL
#define __GCC_ATOMIC_SHORT_LOCK_FREE 2
#define __UINT_FAST8_TYPE__ unsigned char
#define _CALL_ELF 1
#define __ATOMIC_ACQ_REL 4
#define __ATOMIC_RELEASE 3