Merge bitcoin/bitcoin#25425: build: Fix `::_wsystem` check

b5f6a4650334d58245b45eace57f2bc23467ffc7 build: Fix `::_wsystem` check (Hennadii Stepanov)

Pull request description:

  The `::_wsystem` check has been introduced in bitcoin/bitcoin#15457, and it is broken.

  An excerpt from `config.log` for `./autogen.sh && ./configure CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site` on master (a09033e22c4f072c86a1885dd476f3059e5416d1):
  ```
  configure:29111: checking for ::_wsystem
  configure:29125: x86_64-w64-mingw32-g++-posix -std=c++17 -o conftest.exe -pipe -std=c++17 -O2  -I/home/hebasto/git/bitcoin/depends/x86_64-w64-mingw32/include/  -L/home/hebasto/git/bitcoin/depends/x86_64-w64-mingw32/lib  conftest.cpp -lssp -liphlpapi -lshlwapi -lws2_32 -ladvapi32 -luuid -loleaut32 -lole32 -lcomctl32 -lshell32 -lwinmm -lcomdlg32 -lgdi32 -luser32 -lkernel32  >&5
  conftest.cpp: In function 'int main()':
  conftest.cpp:81:15: error: '::_wsystem' has not been declared
     81 |  int nErr = ::_wsystem("");
        |               ^~~~~~~~
  configure:29125: $? = 1
  configure: failed program was:
  | /* confdefs.h */
  | #define PACKAGE_NAME "Bitcoin Core"
  | #define PACKAGE_TARNAME "bitcoin"
  | #define PACKAGE_VERSION "23.99.0"
  | #define PACKAGE_STRING "Bitcoin Core 23.99.0"
  | #define PACKAGE_BUGREPORT "https://github.com/bitcoin/bitcoin/issues"
  | #define PACKAGE_URL "https://bitcoincore.org/"
  | #define HAVE_CXX17 1
  | #define HAVE_STDIO_H 1
  | #define HAVE_STDLIB_H 1
  | #define HAVE_STRING_H 1
  | #define HAVE_INTTYPES_H 1
  | #define HAVE_STDINT_H 1
  | #define HAVE_STRINGS_H 1
  | #define HAVE_SYS_STAT_H 1
  | #define HAVE_SYS_TYPES_H 1
  | #define HAVE_UNISTD_H 1
  | #define STDC_HEADERS 1
  | #define LT_OBJDIR ".libs/"
  | #define USE_ASM 1
  | #define HAVE_CLMUL 1
  | #define ENABLE_SSE41 1
  | #define ENABLE_AVX2 1
  | #define ENABLE_X86_SHANI 1
  | #define HAVE_LIBKERNEL32 1
  | #define HAVE_LIBUSER32 1
  | #define HAVE_LIBGDI32 1
  | #define HAVE_LIBCOMDLG32 1
  | #define HAVE_LIBWINMM 1
  | #define HAVE_LIBSHELL32 1
  | #define HAVE_LIBCOMCTL32 1
  | #define HAVE_LIBOLE32 1
  | #define HAVE_LIBOLEAUT32 1
  | #define HAVE_LIBUUID 1
  | #define HAVE_LIBADVAPI32 1
  | #define HAVE_LIBWS2_32 1
  | #define HAVE_LIBSHLWAPI 1
  | #define HAVE_LIBIPHLPAPI 1
  | #define HAVE_PTHREAD_PRIO_INHERIT 1
  | #define HAVE_PTHREAD 1
  | #define _FILE_OFFSET_BITS 64
  | #define HAVE_DECL_STRERROR_R 0
  | #define HAVE_LIBSSP 1
  | #define HAVE_STDIO_H 1
  | #define HAVE_STDLIB_H 1
  | #define HAVE_UNISTD_H 1
  | #define HAVE_STRINGS_H 1
  | #define HAVE_SYS_TYPES_H 1
  | #define HAVE_SYS_STAT_H 1
  | #define HAVE_DECL_GETIFADDRS 0
  | #define HAVE_DECL_FREEIFADDRS 0
  | #define HAVE_DECL_FORK 0
  | #define HAVE_DECL_SETSID 0
  | #define HAVE_DECL_PIPE2 0
  | #define HAVE_DECL_LE16TOH 0
  | #define HAVE_DECL_LE32TOH 0
  | #define HAVE_DECL_LE64TOH 0
  | #define HAVE_DECL_HTOLE16 0
  | #define HAVE_DECL_HTOLE32 0
  | #define HAVE_DECL_HTOLE64 0
  | #define HAVE_DECL_BE16TOH 0
  | #define HAVE_DECL_BE32TOH 0
  | #define HAVE_DECL_BE64TOH 0
  | #define HAVE_DECL_HTOBE16 0
  | #define HAVE_DECL_HTOBE32 0
  | #define HAVE_DECL_HTOBE64 0
  | #define HAVE_DECL_BSWAP_16 0
  | #define HAVE_DECL_BSWAP_32 0
  | #define HAVE_DECL_BSWAP_64 0
  | #define HAVE_BUILTIN_CLZL 1
  | #define HAVE_BUILTIN_CLZLL 1
  | #define HAVE_DEFAULT_VISIBILITY_ATTRIBUTE 1
  | #define HAVE_DLLEXPORT_ATTRIBUTE 1
  | #define HAVE_FDATASYNC 0
  | #define HAVE_O_CLOEXEC 0
  | /* end confdefs.h.  */
  |
  | int
  | main (void)
  | {
  |  int nErr = ::_wsystem("");
  |
  |   ;
  |   return 0;
  | }
  configure:29130: result: no
  ```

  See https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/system-wsystem

ACKs for top commit:
  laanwj:
    Code review ACK b5f6a4650334d58245b45eace57f2bc23467ffc7

Tree-SHA512: 30cadb7e2e2e3885955ba72c2c27c5dfef2f1b0a9e02e7e811d9bd7cb2c380bab77ca9df3a476d83105de3fa01d043f995e3680b7bff5e7c33829d281b67f374

1 files changed, 2 insertions, 2 deletions

diff --git a/configure.ac b/configure.ac
index a4a23474c8..ffa445b46f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1261,8 +1261,8 @@ AC_LINK_IFELSE(
 AC_MSG_CHECKING([for ::_wsystem])
 AC_LINK_IFELSE(
     [ AC_LANG_PROGRAM(
-        [[ ]],
-        [[ int nErr = ::_wsystem(""); ]]
+        [[ #include <stdlib.h> ]],
+        [[ int nErr = ::_wsystem(NULL); ]]
     )],
     [ AC_MSG_RESULT([yes]); have_any_system=yes],
     [ AC_MSG_RESULT([no]) ]