View gcc default macro definition

Basic commands

Execute the gcc -E -dM test.c command to view the default macro definition of gcc on the current system, where test.c is a c source file with empty content.

Extension

Embedded gcc can add CPU parameters to see the default macro definition of gcc under the current compilation configuration, for example, execute the command arm-none-eabi-gcc -mcpu=cortex-a53 -E -dM test.c -o test. txt You can get the default macro definition of the following context-a53 processor arm-none-eabi-gcc.

#define __DBL_MIN_EXP__ (-1021)
#define __HQ_FBIT__ 15
#define __UINT_LEAST16_MAX__ 0xffff
#define __ARM_SIZEOF_WCHAR_T 4
#define __ATOMIC_ACQUIRE 2
#define __SFRACT_IBIT__ 0
#define __FLT_MIN__ 1.1754943508222875e-38F
#define __GCC_IEC_559_COMPLEX 0
#define __UFRACT_MAX__ 0XFFFFP-16UR
#define __UINT_LEAST8_TYPE__ unsigned char
#define __DQ_FBIT__ 63
#define __INTMAX_C(c) c ## LL
#define __ARM_FEATURE_SAT 1
#define __ULFRACT_FBIT__ 32
#define __CHAR_BIT__ 8
#define __USQ_IBIT__ 0
#define __UINT8_MAX__ 0xff
#define __ACCUM_FBIT__ 15
#define __WINT_MAX__ 0xffffffffU
#define __FLT32_MIN_EXP__ (-125)
#define __USFRACT_FBIT__ 8
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __SIZE_MAX__ 0xffffffffU
#define __ARM_ARCH_ISA_ARM 1
#define __WCHAR_MAX__ 0xffffffffU
#define __LACCUM_IBIT__ 32
#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)4.9406564584124654e-324L)
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
#define __GCC_ATOMIC_CHAR_LOCK_FREE 2
#define __GCC_IEC_559 0
#define __FLT32X_DECIMAL_DIG__ 17
#define __FLT_EVAL_METHOD__ 0
#define __TQ_IBIT__ 0
#define __LLACCUM_MAX__ 0X7FFFFFFFFFFFFFFFP-31LLK
#define __FLT64_DECIMAL_DIG__ 17
#define __GCC_ATOMIC_CHAR32_T_LOCK_FREE 2
#define __UINT_FAST64_MAX__ 0xffffffffffffffffULL
#define __SIG_ATOMIC_TYPE__ int
#define __DBL_MIN_10_EXP__ (-307)
#define __FINITE_MATH_ONLY__ 0
#define __ARMEL__ 1
#define __FLT32X_MAX_EXP__ 1024
#define __LFRACT_IBIT__ 0
#define __GNUC_PATCHLEVEL__ 0
#define __FLT32_HAS_DENORM__ 1
#define __LFRACT_MAX__ 0X7FFFFFFFP-31LR
#define __USA_FBIT__ 16
#define __UINT_FAST8_MAX__ 0xffffffffU
#define __FLT32_MAX_10_EXP__ 38
#define __INT8_C(c) c
#define __INT_LEAST8_WIDTH__ 8
#define __UINT_LEAST64_MAX__ 0xffffffffffffffffULL
#define __SA_FBIT__ 15
#define __SHRT_MAX__ 0x7fff
#define __LDBL_MAX__ 1.7976931348623157e + 308L
#define __ARM_FEATURE_IDIV 1
#define __FRACT_MAX__ 0X7FFFP-15R
#define __LDBL_IS_IEC_60559__ 1
#define __UFRACT_FBIT__ 16
#define __UFRACT_MIN__ 0.0UR
#define __UINT_LEAST8_MAX__ 0xff
#define __GCC_ATOMIC_BOOL_LOCK_FREE 2
#define __UINTMAX_TYPE__ long long unsigned int
#define __LLFRACT_EPSILON__ 0x1P-63LLR
#define __FLT_EVAL_METHOD_TS_18661_3__ 0
#define __UINT32_MAX__ 0xffffffffUL
#define __ULFRACT_MAX__ 0XFFFFFFFFP-32ULR
#define __TA_IBIT__ 64
#define __LDBL_MAX_EXP__ 1024
#define __WINT_MIN__ 0U
#define __FLT32X_IS_IEC_60559__ 1
#define __ARM_ARCH_8A__ 1
#define __INT_LEAST16_WIDTH__ 16
#define __ULLFRACT_MIN__ 0.0ULLR
#define __SCHAR_MAX__ 0x7f
#define __WCHAR_MIN__ 0U
#define __INT64_C(c) c ## LL
#define __GCC_ATOMIC_POINTER_LOCK_FREE 2
#define __ATOMIC_SEQ_CST 5
#define __SIZEOF_INT__ 4
#define __FLT32X_MANT_DIG__ 53
#define __USACCUM_IBIT__ 8
#define __STDC_HOSTED__ 1
#define __LFRACT_MIN__ (-0.5LR-0.5LR)
#define __HA_IBIT__ 8
#define __DBL_DIG__ 15
#define __FLT_EPSILON__ 1.1920928955078125e-7F
#define __APCS_32__ 1
#define __SHRT_WIDTH__ 16
#define __FLT32_IS_IEC_60559__ 1
#define __USFRACT_IBIT__ 0
#define __LDBL_MIN__ 2.2250738585072014e-308L
#define __STDC_UTF_16__ 1
#define __DBL_IS_IEC_60559__ 1
#define __FRACT_MIN__ (-0.5R-0.5R)
#define __DA_IBIT__ 32
#define __ARM_SIZEOF_MINIMAL_ENUM 1
#define __FLT32X_HAS_INFINITY__ 1
#define __INT32_MAX__ 0x7fffffffL
#define __UQQ_FBIT__ 8
#define __INT_WIDTH__ 32
#define __UACCUM_MAX__ 0XFFFFFFFFP-16UK
#define __DECIMAL_DIG__ 17
#define __LFRACT_EPSILON__ 0x1P-31LR
#define __FLT64_EPSILON__ 2.2204460492503131e-16F64
#define __ULFRACT_MIN__ 0.0ULR
#define __LDBL_HAS_QUIET_NAN__ 1
#define __ULACCUM_IBIT__ 32
#define __FLT64_MANT_DIG__ 53
#define __UACCUM_EPSILON__ 0x1P-16UK
#define __GNUC__ 13
#define __ULLACCUM_MAX__ 0XFFFFFFFFFFFFFFFFP-32ULLK
#define __HQ_IBIT__ 0
#define __FLT_HAS_DENORM__ 1
#define __SIZEOF_LONG_DOUBLE__ 8
#define __SA_IBIT__ 16
#define __BIGGEST_ALIGNMENT__ 8
#define __FLT64_MAX_10_EXP__ 308
#define __GNUC_STDC_INLINE__ 1
#define __DQ_IBIT__ 0
#define __DBL_MAX__ ((double)1.7976931348623157e + 308L)
#define __ULFRACT_IBIT__ 0
#define __INT_FAST32_MAX__ 0x7fffffff
#define __DBL_HAS_INFINITY__ 1
#define __HAVE_SPECULATION_SAFE_VALUE 1
#define __ACCUM_IBIT__ 16
#define __THUMB_INTERWORK__ 1
#define __INTPTR_WIDTH__ 32
#define __UINT_LEAST32_MAX__ 0xffffffffUL
#define __LACCUM_MAX__ 0X7FFFFFFFFFFFFFFFP-31LK
#define __FLT32X_HAS_DENORM__ 1
#define __INT_FAST16_TYPE__ int
#define __LDBL_HAS_DENORM__ 1
#define __ARM_FEATURE_LDREX 15
#define __INT_LEAST32_MAX__ 0x7fffffffL
#define __ARM_PCS 1
#define __ACCUM_MAX__ 0X7FFFFFFFP-15K
#define __DBL_MAX_EXP__ 1024
#define __USACCUM_EPSILON__ 0x1P-8UHK
#define __WCHAR_WIDTH__ 32
#define __FLT32_MAX__ 3.4028234663852886e + 38F32
#define __GCC_ATOMIC_LONG_LOCK_FREE 2
#define __SFRACT_MAX__ 0X7FP-7HR
#define __FRACT_IBIT__ 0
#define __PTRDIFF_MAX__ 0x7fffffff
#define __UACCUM_MIN__ 0.0UK
#define __UACCUM_IBIT__ 16
#define __LLACCUM_MIN__ (-0X1P31LLK-0X1P31LLK)
#define __FLT32_HAS_QUIET_NAN__ 1
#define __LONG_LONG_MAX__ 0x7fffffffffffffffLL
#define __ULACCUM_MAX__ 0XFFFFFFFFFFFFFFFFP-32ULK
#define __SIZEOF_WINT_T__ 4
#define __LONG_LONG_WIDTH__ 64
#define __FLT32_MAX_EXP__ 128
#define __ULLACCUM_MIN__ 0.0ULLK
#define __GXX_ABI_VERSION 1018
#define __UTA_FBIT__ 64
#define __FLT_MIN_EXP__ (-125)
#define __UFRACT_IBIT__ 0
#define __INT16_MAX__ 0x7fff
#define __ARM_FEATURE_QBIT 1
#define __INT_FAST64_TYPE__ long long int
#define __FLT64_DENORM_MIN__ 4.9406564584124654e-324F64
#define __DBL_MIN__ ((double)2.2250738585072014e-308L)
#define __SIZEOF_POINTER__ 4
#define __SIZE_TYPE__ unsigned int
#define __DBL_HAS_QUIET_NAN__ 1
#define __FLT32X_EPSILON__ 2.2204460492503131e-16F32x
#define __FLT64_MIN_EXP__ (-1021)
#define __LACCUM_MIN__ (-0X1P31LK-0X1P31LK)
#define __FRACT_FBIT__ 15
#define __ULLACCUM_FBIT__ 32
#define __GXX_TYPEINFO_EQUALITY_INLINE 0
#define __FLT64_MIN_10_EXP__ (-307)
#define __ULLFRACT_EPSILON__ 0x1P-64ULLR
#define __USES_INITFINI__ 1
#define __REGISTER_PREFIX__
#define __UINT16_MAX__ 0xffff
#define __DBL_HAS_DENORM__ 1
#define __ACCUM_MIN__ (-0X1P15K-0X1P15K)
#define __LDBL_HAS_INFINITY__ 1
#define __SQ_IBIT__ 0
#define __FLT32_MIN__ 1.1754943508222875e-38F32
#define __UINT8_TYPE__ unsigned char
#define __UHA_FBIT__ 8
#define __FLT_DIG__ 6
#define __NO_INLINE__ 1
#define __SFRACT_MIN__ (-0.5HR-0.5HR)
#define __UTQ_FBIT__ 128
#define __DEC_EVAL_METHOD__ 2
#define __FLT_MANT_DIG__ 24
#define __LDBL_DECIMAL_DIG__ 17
#define __VERSION__ "13.2.0"
#define __UINT64_C(c) c ## ULL
#define __ULLFRACT_FBIT__ 64
#define __SOFTFP__ 1
#define __FRACT_EPSILON__ 0x1P-15R
#define __ULACCUM_MIN__ 0.0ULK
#define __UDA_FBIT__ 32
#define __LLACCUM_EPSILON__ 0x1P-31LLK
#define __GCC_ATOMIC_INT_LOCK_FREE 2
#define __FLOAT_WORD_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __USFRACT_MIN__ 0.0UHR
#define __FLT32_MANT_DIG__ 24
#define __UQQ_IBIT__ 0
#define __USFRACT_MAX__ 0XFFP-8UHR
#define __SCHAR_WIDTH__ 8
#define __INT32_C(c) c ## L
#define __ORDER_PDP_ENDIAN__ 3412
#define __UHQ_FBIT__ 16
#define __LLACCUM_FBIT__ 31
#define __INT_FAST32_TYPE__ int
#define __UINT_LEAST16_TYPE__ short unsigned int
#define __UINT64_MAX__ 0xffffffffffffffffULL
#define __FLT_IS_IEC_60559__ 1
#define __UDQ_FBIT__ 64
#define __GNUC_WIDE_EXECUTION_CHARSET_NAME "UTF-32LE"
#define __INT8_TYPE__ signed char
#define __ELF__ 1
#define __GCC_ASM_FLAG_OUTPUTS__ 1
#define __SACCUM_EPSILON__ 0x1P-7HK
#define __ULFRACT_EPSILON__ 0x1P-32ULR
#define __LLFRACT_FBIT__ 63
#define __FLT_RADIX__ 2
#define __INT_LEAST16_TYPE__ short int
#define __ARM_ARCH_PROFILE 65
#define __LDBL_EPSILON__ 2.2204460492503131e-16L
#define __UINTMAX_C(c) c ## ULL
#define __SACCUM_MAX__ 0X7FFFP-7HK
#define __FLT32X_MIN__ 2.2250738585072014e-308F32x
#define __SIG_ATOMIC_MAX__ 0x7fffffff
#define __UACCUM_FBIT__ 16
#define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2
#define __USER_LABEL_PREFIX__
#define __VFP_FP__ 1
#define __SIZEOF_PTRDIFF_T__ 4
#define __FLT32_HAS_INFINITY__ 1
#define __SIZEOF_LONG__ 4
#define __LACCUM_EPSILON__ 0x1P-31LK
#define __LDBL_DIG__ 15
#define __FLT64_IS_IEC_60559__ 1
#define __FLT32X_MIN_EXP__ (-1021)
#define __INT_FAST16_MAX__ 0x7fffffff
#define __GCC_CONSTRUCTIVE_SIZE 64
#define __FLT64_DIG__ 15
#define __UINT_FAST32_MAX__ 0xffffffffU
#define __UINT_LEAST64_TYPE__ long long unsigned int
#define __SFRACT_EPSILON__ 0x1P-7HR
#define __FLT_HAS_QUIET_NAN__ 1
#define __FLT_MAX_10_EXP__ 38
#define __LONG_MAX__ 0x7fffffffL
#define __SIZEOF_SIZE_T__ 4
#define __FLT_HAS_INFINITY__ 1
#define __GNUC_EXECUTION_CHARSET_NAME "UTF-8"
#define __CHAR_UNSIGNED__ 1
#define __UINT_FAST16_TYPE__ unsigned int
#define __ARM_32BIT_STATE 1
#define __INT_FAST32_WIDTH__ 32
#define __CHAR16_TYPE__ short unsigned int
#define __PRAGMA_REDEFINE_EXTNAME 1
#define __SIZE_WIDTH__ 32
#define __INT_LEAST16_MAX__ 0x7fff
#define __INT64_MAX__ 0x7ffffffffffffffffLL
#define __SACCUM_FBIT__ 7
#define __FLT32_DENORM_MIN__ 1.4012984643248171e-45F32
#define __SIG_ATOMIC_WIDTH__ 32
#define __INT_LEAST64_TYPE__ long long int
#define __ARM_FEATURE_CLZ 1
#define __INT16_TYPE__ short int
#define __INT_LEAST8_TYPE__ signed char
#define __STDC_VERSION__ 201710L
#define __SQ_FBIT__ 31
#define __ARM_ARCH_ISA_THUMB 2
#define __INT_FAST8_MAX__ 0x7fffffff
#define __ARM_ARCH 8
#define __INTPTR_MAX__ 0x7fffffff
#define __QQ_FBIT__ 7
#define __UTA_IBIT__ 64
#define __FLT64_HAS_QUIET_NAN__ 1
#define __FLT32_MIN_10_EXP__ (-37)
#define __FLT32X_DIG__ 15
#define __UINT16_C(c) c
#define __PTRDIFF_WIDTH__ 32
#define __LDBL_MANT_DIG__ 53
#define __SFRACT_FBIT__ 7
#define __SACCUM_MIN__ (-0X1P7HK-0X1P7HK)
#define __FLT64_HAS_INFINITY__ 1
#define __SIG_ATOMIC_MIN__ (-__SIG_ATOMIC_MAX__ - 1)
#define __INTPTR_TYPE__ int
#define __UINT16_TYPE__ short unsigned int
#define __WCHAR_TYPE__ unsigned int
#define __SIZEOF_FLOAT__ 4
#define __TQ_FBIT__ 127
#define __USQ_FBIT__ 32
#define __UINTPTR_MAX__ 0xffffffffU
#define __INT_FAST64_WIDTH__ 64
#define __ARM_FEATURE_UNALIGNED 1
#define __ULLACCUM_IBIT__ 32
#define __FLT32_DECIMAL_DIG__ 9
#define __INT_FAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_TEST_AND_SET_TRUEVAL 1
#define __FLT_NORM_MAX__ 3.4028234663852886e + 38F
#define __UINT_FAST64_TYPE__ long long unsigned int
#define __INT_MAX__ 0x7fffffff
#define __LACCUM_FBIT__ 31
#define __USACCUM_MIN__ 0.0UHK
#define __UHA_IBIT__ 8
#define __INT64_TYPE__ long long int
#define __FLT_MAX_EXP__ 128
#define __UTQ_IBIT__ 0
#define __DBL_MANT_DIG__ 53
#define __INT_LEAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2
#define __WINT_TYPE__ unsigned int
#define __UINT_LEAST32_TYPE__ long unsigned int
#define __SIZEOF_SHORT__ 2
#define __ULLFRACT_IBIT__ 0
#define __FLT32_NORM_MAX__ 3.4028234663852886e + 38F32
#define __LDBL_MIN_EXP__ (-1021)
#define __arm__ 1
#define __FLT64_MAX__ 1.7976931348623157e + 308F64
#define __UDA_IBIT__ 32
#define __WINT_WIDTH__ 32
#define __INT_LEAST8_MAX__ 0x7f
#define __INT_LEAST64_WIDTH__ 64
#define __FLT32X_MAX_10_EXP__ 308
#define __LFRACT_FBIT__ 31
#define __LDBL_MAX_10_EXP__ 308
#define __ATOMIC_RELAXED 0
#define __DBL_EPSILON__ ((double)2.2204460492503131e-16L)
#define __INT_LEAST32_TYPE__ long int
#define __ARM_FEATURE_SIMD32 1
#define __UINT8_C(c) c
#define __FLT64_MAX_EXP__ 1024
#define __SIZEOF_WCHAR_T__ 4
#define __UINT64_TYPE__ long long unsigned int
#define __ARM_FEATURE_CRC32 1
#define __LLFRACT_MAX__ 0X7FFFFFFFFFFFFFFFP-63LLR
#define __FLT64_NORM_MAX__ 1.7976931348623157e + 308F64
#define __INTMAX_MAX__ 0x7ffffffffffffffffLL
#define __INT_FAST8_TYPE__ int
#define __ULLACCUM_EPSILON__ 0x1P-32ULLK
#define __USACCUM_MAX__ 0XFFFFP-8UHK
#define __UHQ_IBIT__ 0
#define __LLACCUM_IBIT__ 32
#define __FLT64_HAS_DENORM__ 1
#define __FLT32_EPSILON__ 1.1920928955078125e-7F32
#define __DBL_DECIMAL_DIG__ 17
#define __STDC_UTF_32__ 1
#define __INT_FAST8_WIDTH__ 32
#define __FLT32X_MAX__ 1.7976931348623157e + 308F32x
#define __TA_FBIT__ 63
#define __DBL_NORM_MAX__ ((double)1.7976931348623157e + 308L)
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __GCC_DESTRUCTIVE_SIZE 64
#define __UDQ_IBIT__ 0
#define __INTMAX_WIDTH__ 64
#define __ORDER_BIG_ENDIAN__ 4321
#define __ARM_FEATURE_DSP 1
#define __FLT32_DIG__ 6
#define __ACCUM_EPSILON__ 0x1P-15K
#define __UINT32_C(c) c ## UL
#define __FLT_DENORM_MIN__ 1.4012984643248171e-45F
#define __LLFRACT_IBIT__ 0
#define __INT8_MAX__ 0x7f
#define __LONG_WIDTH__ 32
#define __UINT_FAST32_TYPE__ unsigned int
#define __FLT32X_NORM_MAX__ 1.7976931348623157e + 308F32x
#define __CHAR32_TYPE__ long unsigned int
#define __FLT_MAX__ 3.4028234663852886e + 38F
#define __USACCUM_FBIT__ 8
#define __INT32_TYPE__ long int
#define __SIZEOF_DOUBLE__ 8
#define __FLT_MIN_10_EXP__ (-37)
#define __UFRACT_EPSILON__ 0x1P-16UR
#define __FLT64_MIN__ 2.2250738585072014e-308F64
#define __INT_LEAST32_WIDTH__ 32
#define __INTMAX_TYPE__ long long int
#define __FLT32X_HAS_QUIET_NAN__ 1
#define __ATOMIC_CONSUME 1
#define __GNUC_MINOR__ 2
#define __INT_FAST16_WIDTH__ 32
#define __UINTMAX_MAX__ 0xffffffffffffffffULL
#define __FLT32X_DENORM_MIN__ 4.9406564584124654e-324F32x
#define __HA_FBIT__ 7
#define __DBL_MAX_10_EXP__ 308
#define __LDBL_DENORM_MIN__ 4.9406564584124654e-324L
#define __INT16_C(c) c
#define __STDC__ 1
#define __PTRDIFF_TYPE__ int
#define __LLFRACT_MIN__ (-0.5LLR-0.5LLR)
#define __DA_FBIT__ 31
#define __UINT32_TYPE__ long unsigned int
#define __FLT32X_MIN_10_EXP__ (-307)
#define __ARM_ARCH_EXT_IDIV__ 1
#define __UINTPTR_TYPE__ unsigned int
#define __USA_IBIT__ 16
#define __ARM_EABI__ 1
#define __LDBL_MIN_10_EXP__ (-307)
#define __SIZEOF_LONG_LONG__ 8
#define __ULACCUM_EPSILON__ 0x1P-32ULK
#define __SACCUM_IBIT__ 8
#define __GCC_ATOMIC_LLONG_LOCK_FREE 2
#define __FLT_DECIMAL_DIG__ 9
#define __UINT_FAST16_MAX__ 0xffffffffU
#define __LDBL_NORM_MAX__ 1.7976931348623157e + 308L
#define __GCC_ATOMIC_SHORT_LOCK_FREE 2
#define __ULLFRACT_MAX__ 0XFFFFFFFFFFFFFFFFP-64ULLR
#define __UINT_FAST8_TYPE__ unsigned int
#define __USFRACT_EPSILON__ 0x1P-8UHR
#define __ULACCUM_FBIT__ 32
#define __QQ_IBIT__ 0
#define __ATOMIC_ACQ_REL 4
#define __ATOMIC_RELEASE 3