MSYS2/MinGW-w64: Missing Header 'alloca.h'

[AntumDeluge]

OS: Windows 10 64-bit
Environment: MSYS2/MinGW-w64
Geany source: f0e3ee2

My compiler complains that the alloca.h header is missing.

FAILED: libregex.a.p/ctags_gnu_regex_regex.c.obj
"cc" "-Ilibregex.a.p" "-I." "-I.." "-I../ctags/fnmatch" "-fdiagnostics-color=always" "-D_FILE_OFFSET_BITS=64" "-Wall" "-Winvalid-pch" "-std=c11" "-O3
" "-DHAVE_CONFIG_H=1" "-O2" "-D__USE_GNU" -MD -MQ libregex.a.p/ctags_gnu_regex_regex.c.obj -MF "libregex.a.p/ctags_gnu_regex_regex.c.obj.d" -o libreg
ex.a.p/ctags_gnu_regex_regex.c.obj "-c" ../ctags/gnu_regex/regex.c
In file included from ../ctags/gnu_regex/regex.c:61:
../ctags/gnu_regex/regex_internal.h:424:11: fatal error: alloca.h: No such file or directory
  424 | # include <alloca.h>
      |           ^~~~~~~~~~
compilation terminated.

According to this answer on SO, alloca.h does not exist in Windows & should be replaced with malloc.h.

I haven't tested it yet. Wanted to get the report posted.

Edit: This is an issue with my system, not Geany. The code defines the following:

#ifdef WIN32
# include <malloc.h>
#else
# include <alloca.h>
#endif

It appears my MSYS2/MinGW-w64 compiler is not defining WIN32. Which seems strange as I thought it did.

Edit: I will close this soon.

Edit: It is defined. I wonder why the compiler isn't complying with it.

$ echo | gcc -dM -E -
#define __DBL_MIN_EXP__ (-1021)
#define __UINT_LEAST16_MAX__ 0xffff
#define __FLT16_HAS_QUIET_NAN__ 1
#define __ATOMIC_ACQUIRE 2
#define __FLT128_MAX_10_EXP__ 4932
#define __FLT_MIN__ 1.17549435082228750796873653722224568e-38F
#define __GCC_IEC_559_COMPLEX 2
#define __UINT_LEAST8_TYPE__ unsigned char
#define __SIZEOF_FLOAT80__ 16
#define __INTMAX_C(c) c ## LL
#define __CHAR_BIT__ 8
#define __MINGW32__ 1
#define __UINT8_MAX__ 0xff
#define __SCHAR_WIDTH__ 8
#define _WIN64 1
#define __WINT_MAX__ 0xffff
#define __FLT32_MIN_EXP__ (-125)
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __SIZE_MAX__ 0xffffffffffffffffULL
#define __WCHAR_MAX__ 0xffff
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
#define __GCC_ATOMIC_CHAR_LOCK_FREE 2
#define __GCC_IEC_559 2
#define __FLT32X_DECIMAL_DIG__ 17
#define __FLT_EVAL_METHOD__ 0
#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 __FLT32X_MAX_EXP__ 1024
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1
#define __FLT32_HAS_DENORM__ 1
#define __UINT_FAST8_MAX__ 0xff
#define __FLT32_MAX_10_EXP__ 38
#define _stdcall __attribute__((__stdcall__))
#define __DEC64_MAX_EXP__ 385
#define __INT8_C(c) c
#define __INT_LEAST8_WIDTH__ 8
#define __UINT_LEAST64_MAX__ 0xffffffffffffffffULL
#define __SHRT_MAX__ 0x7fff
#define __LDBL_MAX__ 1.18973149535723176502126385303097021e+4932L
#define __FLT64X_MAX_10_EXP__ 4932
#define __LDBL_IS_IEC_60559__ 2
#define __FLT64X_HAS_QUIET_NAN__ 1
#define __UINT_LEAST8_MAX__ 0xff
#define __GCC_ATOMIC_BOOL_LOCK_FREE 2
#define __FLT128_DENORM_MIN__ 6.47517511943802511092443895822764655e-4966F128
#define __UINTMAX_TYPE__ long long unsigned int
#define __DEC32_EPSILON__ 1E-6DF
#define __FLT_EVAL_METHOD_TS_18661_3__ 0
#define __UINT32_MAX__ 0xffffffffU
#define __DBL_DENORM_MIN__ ((double)4.94065645841246544176568792868221372e-324L)
#define __FLT128_MIN_EXP__ (-16381)
#define __WINT_MIN__ 0
#define __FLT128_MIN_10_EXP__ (-4931)
#define __FLT32X_IS_IEC_60559__ 2
#define __INT_LEAST16_WIDTH__ 16
#define __SCHAR_MAX__ 0x7f
#define __FLT128_MANT_DIG__ 113
#define __WCHAR_MIN__ 0
#define __INT64_C(c) c ## LL
#define __GCC_ATOMIC_POINTER_LOCK_FREE 2
#define __FLT32X_MANT_DIG__ 53
#define __FLT64X_EPSILON__ 1.08420217248550443400745280086994171e-19F64x
#define __STDC_HOSTED__ 1
#define __DEC64_MIN_EXP__ (-382)
#define __WIN64 1
#define __DBL_DIG__ 15
#define __FLT32_DIG__ 6
#define __FLT_EPSILON__ 1.19209289550781250000000000000000000e-7F
#define __SHRT_WIDTH__ 16
#define __FLT32_IS_IEC_60559__ 2
#define __LDBL_MIN__ 3.36210314311209350626267781732175260e-4932L
#define __STDC_UTF_16__ 1
#define __DBL_IS_IEC_60559__ 2
#define __DEC32_MAX__ 9.999999E96DF
#define __FLT64X_DENORM_MIN__ 3.64519953188247460252840593361941982e-4951F64x
#define __FLT32X_HAS_INFINITY__ 1
#define __INT32_MAX__ 0x7fffffff
#define __FLT16_DIG__ 3
#define __INT_WIDTH__ 32
#define __SIZEOF_LONG__ 4
#define __UINT16_C(c) c
#define __DECIMAL_DIG__ 21
#define __FLT64_EPSILON__ 2.22044604925031308084726333618164062e-16F64
#define __FLT128_IS_IEC_60559__ 2
#define __FLT64X_MIN_10_EXP__ (-4931)
#define __LDBL_HAS_QUIET_NAN__ 1
#define __FLT16_MIN_EXP__ (-13)
#define __FLT64_MANT_DIG__ 53
#define _REENTRANT 1
#define __FLT64X_MANT_DIG__ 64
#define __GNUC__ 12
#define _cdecl __attribute__((__cdecl__))
#define __MMX__ 1
#define __FLT_HAS_DENORM__ 1
#define __SIZEOF_LONG_DOUBLE__ 16
#define __BIGGEST_ALIGNMENT__ 16
#define __FLT64_MAX_10_EXP__ 308
#define __FLT16_MAX_10_EXP__ 4
#define __DBL_MAX__ ((double)1.79769313486231570814527423731704357e+308L)
#define _thiscall __attribute__((__thiscall__))
#define __INT_FAST32_MAX__ 0x7fffffff
#define __WINNT 1
#define __DBL_HAS_INFINITY__ 1
#define __SIZEOF_FLOAT__ 4
#define __WINNT__ 1
#define __HAVE_SPECULATION_SAFE_VALUE 1
#define __DEC32_MIN_EXP__ (-94)
#define __INTPTR_WIDTH__ 64
#define __FLT64X_HAS_INFINITY__ 1
#define __UINT_LEAST32_MAX__ 0xffffffffU
#define __FLT32X_HAS_DENORM__ 1
#define __INT_FAST16_TYPE__ short int
#define __MMX_WITH_SSE__ 1
#define _fastcall __attribute__((__fastcall__))
#define __LDBL_HAS_DENORM__ 1
#define __SEG_GS 1
#define __FLT128_HAS_INFINITY__ 1
#define __DEC32_MIN__ 1E-95DF
#define __DBL_MAX_EXP__ 1024
#define __WCHAR_WIDTH__ 16
#define __FLT32_MAX__ 3.40282346638528859811704183484516925e+38F32
#define __DEC128_EPSILON__ 1E-33DL
#define __FLT16_DECIMAL_DIG__ 5
#define __SSE2_MATH__ 1
#define __ATOMIC_HLE_RELEASE 131072
#define __WIN32__ 1
#define __PTRDIFF_MAX__ 0x7fffffffffffffffLL
#define __amd64 1
#define __ATOMIC_HLE_ACQUIRE 65536
#define __LONG_LONG_MAX__ 0x7fffffffffffffffLL
#define __SIZEOF_SIZE_T__ 8
#define __FLT64X_MIN_EXP__ (-16381)
#define __SIZEOF_WINT_T__ 2
#define __LONG_LONG_WIDTH__ 64
#define __FLT32_MAX_EXP__ 128
#define __GXX_ABI_VERSION 1017
#define __FLT_MIN_EXP__ (-125)
#define __INT16_MAX__ 0x7fff
#define __x86_64 1
#define __INT_FAST64_TYPE__ long long int
#define __FLT64_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F64
#define __DBL_MIN__ ((double)2.22507385850720138309023271733240406e-308L)
#define __FLT16_DENORM_MIN__ 5.96046447753906250000000000000000000e-8F16
#define __FLT128_EPSILON__ 1.92592994438723585305597794258492732e-34F128
#define __FLT64X_NORM_MAX__ 1.18973149535723176502126385303097021e+4932F64x
#define __SIZEOF_POINTER__ 8
#define __SIZE_TYPE__ long long unsigned int
#define __DBL_HAS_QUIET_NAN__ 1
#define __FLT32X_EPSILON__ 2.22044604925031308084726333618164062e-16F32x
#define __DECIMAL_BID_FORMAT__ 1
#define __FLT64_MIN_EXP__ (-1021)
#define __GXX_TYPEINFO_EQUALITY_INLINE 0
#define __FLT64_MIN_10_EXP__ (-307)
#define __FLT16_MIN_10_EXP__ (-4)
#define __FLT64X_DECIMAL_DIG__ 21
#define __DEC128_MIN__ 1E-6143DL
#define __REGISTER_PREFIX__
#define __UINT16_MAX__ 0xffff
#define __DBL_HAS_DENORM__ 1
#define __cdecl __attribute__((__cdecl__))
#define __LDBL_HAS_INFINITY__ 1
#define __FLT32_MIN__ 1.17549435082228750796873653722224568e-38F32
#define __UINT8_TYPE__ unsigned char
#define __FLT_DIG__ 6
#define __NO_INLINE__ 1
#define __DEC_EVAL_METHOD__ 2
#define __DEC128_MAX__ 9.999999999999999999999999999999999E6144DL
#define __FLT_MANT_DIG__ 24
#define __LDBL_DECIMAL_DIG__ 21
#define __VERSION__ "12.2.0"
#define __UINT64_C(c) c ## ULL
#define _WIN32 1
#define __SEH__ 1
#define __INT_LEAST32_MAX__ 0x7fffffff
#define __GCC_ATOMIC_INT_LOCK_FREE 2
#define __FLT128_MAX_EXP__ 16384
#define __FLT32_MANT_DIG__ 24
#define __FLOAT_WORD_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __FLT32X_MIN_EXP__ (-1021)
#define __FLT128_HAS_DENORM__ 1
#define __FLT32_DECIMAL_DIG__ 9
#define __FLT128_DIG__ 33
#define __INT32_C(c) c
#define __DEC64_EPSILON__ 1E-15DD
#define __ORDER_PDP_ENDIAN__ 3412
#define __DEC128_MIN_EXP__ (-6142)
#define __INT_FAST32_TYPE__ int
#define __UINT_LEAST16_TYPE__ short unsigned int
#define __UINT64_MAX__ 0xffffffffffffffffULL
#define __FLT_IS_IEC_60559__ 2
#define __GNUC_WIDE_EXECUTION_CHARSET_NAME "UTF-16LE"
#define __FLT64X_DIG__ 18
#define __INT8_TYPE__ signed char
#define __GCC_ASM_FLAG_OUTPUTS__ 1
#define __UINT32_TYPE__ unsigned int
#define __FLT_RADIX__ 2
#define __INT_LEAST16_TYPE__ short int
#define __LDBL_EPSILON__ 1.08420217248550443400745280086994171e-19L
#define __UINTMAX_C(c) c ## ULL
#define __SSE_MATH__ 1
#define __FLT32X_MIN__ 2.22507385850720138309023271733240406e-308F32x
#define __SIG_ATOMIC_MAX__ 0x7fffffff
#define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2
#define __USER_LABEL_PREFIX__
#define __SIZEOF_PTRDIFF_T__ 8
#define __LDBL_DIG__ 18
#define __FLT64_IS_IEC_60559__ 2
#define __x86_64__ 1
#define __FLT16_IS_IEC_60559__ 2
#define __FLT16_MAX_EXP__ 16
#define __DEC32_SUBNORMAL_MIN__ 0.000001E-95DF
#define __MSVCRT__ 1
#define __INT_FAST16_MAX__ 0x7fff
#define __GCC_CONSTRUCTIVE_SIZE 64
#define __FLT64_DIG__ 15
#define __UINT_FAST32_MAX__ 0xffffffffU
#define __UINT_LEAST64_TYPE__ long long unsigned int
#define __FLT16_EPSILON__ 9.76562500000000000000000000000000000e-4F16
#define __FLT_HAS_QUIET_NAN__ 1
#define __FLT_MAX_10_EXP__ 38
#define __LONG_MAX__ 0x7fffffffL
#define __FLT64X_HAS_DENORM__ 1
#define __DEC128_SUBNORMAL_MIN__ 0.000000000000000000000000000000001E-6143DL
#define __FLT_HAS_INFINITY__ 1
#define __GNUC_EXECUTION_CHARSET_NAME "UTF-8"
#define __UINT_FAST16_TYPE__ short unsigned int
#define __DEC64_MAX__ 9.999999999999999E384DD
#define __INT_FAST32_WIDTH__ 32
#define __CHAR16_TYPE__ short unsigned int
#define __PRAGMA_REDEFINE_EXTNAME 1
#define __SIZE_WIDTH__ 64
#define __SEG_FS 1
#define __INT_LEAST16_MAX__ 0x7fff
#define __FLT16_NORM_MAX__ 6.55040000000000000000000000000000000e+4F16
#define __DEC64_MANT_DIG__ 16
#define __INT64_MAX__ 0x7fffffffffffffffLL
#define __FLT32_DENORM_MIN__ 1.40129846432481707092372958328991613e-45F32
#define __SIG_ATOMIC_WIDTH__ 32
#define __INT_LEAST64_TYPE__ long long int
#define __INT16_TYPE__ short int
#define __INT_LEAST8_TYPE__ signed char
#define __FLT16_MAX__ 6.55040000000000000000000000000000000e+4F16
#define __nocona__ 1
#define __STDC_VERSION__ 201710L
#define __SIZEOF_INT__ 4
#define __DEC32_MAX_EXP__ 97
#define __INT_FAST8_MAX__ 0x7f
#define __FLT128_MAX__ 1.18973149535723176508575932662800702e+4932F128
#define __INTPTR_MAX__ 0x7fffffffffffffffLL
#define __FLT64_HAS_QUIET_NAN__ 1
#define __stdcall __attribute__((__stdcall__))
#define __FLT32_MIN_10_EXP__ (-37)
#define __FLT32X_DIG__ 15
#define __GXX_MERGED_TYPEINFO_NAMES 0
#define __PTRDIFF_WIDTH__ 64
#define __LDBL_MANT_DIG__ 64
#define __FLT64_HAS_INFINITY__ 1
#define __FLT64X_MAX__ 1.18973149535723176502126385303097021e+4932F64x
#define __FLT16_HAS_INFINITY__ 1
#define __SIG_ATOMIC_MIN__ (-__SIG_ATOMIC_MAX__ - 1)
#define __GCC_ATOMIC_LONG_LOCK_FREE 2
#define __DEC32_MANT_DIG__ 7
#define __FLT16_MANT_DIG__ 11
#define __INTPTR_TYPE__ long long int
#define __UINT16_TYPE__ short unsigned int
#define __WCHAR_TYPE__ short unsigned int
#define __pic__ 1
#define __UINTPTR_MAX__ 0xffffffffffffffffULL
#define __INT_FAST64_WIDTH__ 64
#define __INT_FAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_TEST_AND_SET_TRUEVAL 1
#define __FLT_NORM_MAX__ 3.40282346638528859811704183484516925e+38F
#define __FLT32_HAS_INFINITY__ 1
#define __FLT64X_MAX_EXP__ 16384
#define __UINT_FAST64_TYPE__ long long unsigned int
#define __INT_MAX__ 0x7fffffff
#define WIN32 1
#define __nocona 1
#define __code_model_medium__ 1
#define __INT64_TYPE__ long long int
#define __FLT_MAX_EXP__ 128
#define WIN64 1
#define __ORDER_BIG_ENDIAN__ 4321
#define __DBL_MANT_DIG__ 53
#define __SIZEOF_FLOAT128__ 16
#define __INT_LEAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2
#define __DEC64_MIN__ 1E-383DD
#define __WINT_TYPE__ short unsigned int
#define __UINT_LEAST32_TYPE__ unsigned int
#define __SIZEOF_SHORT__ 2
#define __FLT32_NORM_MAX__ 3.40282346638528859811704183484516925e+38F32
#define __SSE__ 1
#define __LDBL_MIN_EXP__ (-16381)
#define __FLT64_MAX__ 1.79769313486231570814527423731704357e+308F64
#define __amd64__ 1
#define __WINT_WIDTH__ 16
#define __INT_LEAST8_MAX__ 0x7f
#define __INT_LEAST64_WIDTH__ 64
#define __LDBL_MAX_EXP__ 16384
#define __FLT32X_MAX_10_EXP__ 308
#define __WIN32 1
#define __SIZEOF_INT128__ 16
#define __FLT16_MIN__ 6.10351562500000000000000000000000000e-5F16
#define __FLT64X_IS_IEC_60559__ 2
#define __LDBL_MAX_10_EXP__ 4932
#define __ATOMIC_RELAXED 0
#define __DBL_EPSILON__ ((double)2.22044604925031308084726333618164062e-16L)
#define __thiscall __attribute__((__thiscall__))
#define __FLT128_MIN__ 3.36210314311209350626267781732175260e-4932F128
#define __UINT8_C(c) c
#define __FLT64_MAX_EXP__ 1024
#define __INT_LEAST32_TYPE__ int
#define __SIZEOF_WCHAR_T__ 2
#define __UINT64_TYPE__ long long unsigned int
#define __GNUC_PATCHLEVEL__ 0
#define __FLT128_NORM_MAX__ 1.18973149535723176508575932662800702e+4932F128
#define __FLT64_NORM_MAX__ 1.79769313486231570814527423731704357e+308F64
#define __FLT128_HAS_QUIET_NAN__ 1
#define __INTMAX_MAX__ 0x7fffffffffffffffLL
#define __INT_FAST8_TYPE__ signed char
#define __fastcall __attribute__((__fastcall__))
#define __FLT64X_MIN__ 3.36210314311209350626267781732175260e-4932F64x
#define __GNUC_STDC_INLINE__ 1
#define __FLT64_HAS_DENORM__ 1
#define __FLT32_EPSILON__ 1.19209289550781250000000000000000000e-7F32
#define __FLT16_HAS_DENORM__ 1
#define __DBL_DECIMAL_DIG__ 17
#define __STDC_UTF_32__ 1
#define __INT_FAST8_WIDTH__ 8
#define __FXSR__ 1
#define __FLT32X_MAX__ 1.79769313486231570814527423731704357e+308F32x
#define __DBL_NORM_MAX__ ((double)1.79769313486231570814527423731704357e+308L)
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __MINGW64__ 1
#define __GCC_DESTRUCTIVE_SIZE 64
#define __INTMAX_WIDTH__ 64
#define __UINT32_C(c) c ## U
#define WINNT 1
#define __FLT_DENORM_MIN__ 1.40129846432481707092372958328991613e-45F
#define __INT8_MAX__ 0x7f
#define __LONG_WIDTH__ 32
#define __PIC__ 1
#define __UINT_FAST32_TYPE__ unsigned int
#define __FLT32X_NORM_MAX__ 1.79769313486231570814527423731704357e+308F32x
#define __CHAR32_TYPE__ unsigned int
#define __FLT_MAX__ 3.40282346638528859811704183484516925e+38F
#define __SSE2__ 1
#define __INT32_TYPE__ int
#define __SIZEOF_DOUBLE__ 8
#define __FLT_MIN_10_EXP__ (-37)
#define __FLT64_MIN__ 2.22507385850720138309023271733240406e-308F64
#define __INT_LEAST32_WIDTH__ 32
#define __INTMAX_TYPE__ long long int
#define _INTEGRAL_MAX_BITS 64
#define __DEC128_MAX_EXP__ 6145
#define __FLT32X_HAS_QUIET_NAN__ 1
#define __ATOMIC_CONSUME 1
#define __GNUC_MINOR__ 2
#define __INT_FAST16_WIDTH__ 16
#define __UINTMAX_MAX__ 0xffffffffffffffffULL
#define __FLT32X_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F32x
#define __DBL_MAX_10_EXP__ 308
#define __LDBL_DENORM_MIN__ 3.64519953188247460252840593361941982e-4951L
#define __INT16_C(c) c
#define __STDC__ 1
#define __PTRDIFF_TYPE__ long long int
#define __ATOMIC_SEQ_CST 5
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16 1
#define __FLT32X_MIN_10_EXP__ (-307)
#define __UINTPTR_TYPE__ long long unsigned int
#define __DEC64_SUBNORMAL_MIN__ 0.000000000000001E-383DD
#define __DEC128_MANT_DIG__ 34
#define __LDBL_MIN_10_EXP__ (-4931)
#define __SIZEOF_LONG_LONG__ 8
#define __FLT128_DECIMAL_DIG__ 36
#define __GCC_ATOMIC_LLONG_LOCK_FREE 2
#define __FLT32_HAS_QUIET_NAN__ 1
#define __FLT_DECIMAL_DIG__ 9
#define __UINT_FAST16_MAX__ 0xffff
#define __LDBL_NORM_MAX__ 1.18973149535723176502126385303097021e+4932L
#define __GCC_ATOMIC_SHORT_LOCK_FREE 2
#define __SSE3__ 1
#define __UINT_FAST8_TYPE__ unsigned char
#define __WIN64__ 1
#define __ATOMIC_ACQ_REL 4
#define __ATOMIC_RELEASE 3
#define __declspec(x) __attribute__((x))

[eht16]

My local MSYS2 setup on a native Windows system does not have alloca.h nor does the CI build image has it (https://github.com/geany/infrastructure/pkgs/container/geany-mingw64-ci) and both cleanly build Geany.

How do you start your build?
Is the gcc command you posted above the same which is used to build Geany?

Just in case you didn't know, there is a howto on https://wiki.geany.org/howtos/win32/msys2 to assist in building Geany with MSYS2.

[AntumDeluge]

@eht16 Thanks for the response. I switched to GNU Autotools & the build succeeded. I didn't realize that building with Meson is still experimental.

Is the gcc command you posted above the same which is used to build Geany?

I'll have to do some digging to make sure.

[AntumDeluge]

According to the Meson log, it's calling cc, which I believe is just a copy of the gcc executable:

$ which cc
/mingw64/bin/cc

$ ls -l /mingw64/bin/[^g]*cc.exe
-rwxr-xr-x 1 antum antum 2350907 Jan 23 00:22 /mingw64/bin/x86_64-w64-mingw32-cc.exe
-rwxr-xr-x 1 antum antum 2350907 Jan 23 00:22 /mingw64/bin/x86_64-w64-mingw32-gcc.exe

It also defines WIN32 as 1.

[eht16]

That you are using Meson is an important bit of information.

I can reproduce the error when using Meson on Windows/MSYS2. And this is because our Meson setup does not WIN32.

The following patch defines it and the build succeeds:

diff --git a/meson.build b/meson.build
index 6944a423b..bf725bd9b 100644
--- a/meson.build
+++ b/meson.build
@@ -202,6 +202,10 @@ if (gnu_source)
        basic_cflags += '-D_GNU_SOURCE'
 endif

+if host_machine.system() == 'windows'
+       basic_cflags += '-DWIN32=1'
+endif
+
 # CFLAGS common between Geany and bundled plugins
 def_cflags = basic_cflags + [
        '-DGTK',

This raises two questions, mainly targeted to @kugel-:

• why did this not fail in the past when we tested Meson support on Windows?
• is there a better way or place in meson.build to add the define?

[AntumDeluge]

That you are using Meson is an important bit of information.

My apologies for not being clear. When I opened this, I thought meson was the recommended build tool.