I see a build error when building GDB under msys+mingw gcc 32bit:
 g++ -x c++ -std=gnu++11 -g -O2    -I. -I../../../binutils-gdb/gdb/gdbserver -I../../../binutils-gdb/gdb/gdbserver/../common -I../../../binutils-gdb/gdb/gdbserver/../regformats -I../../../binutils-gdb/gdb/gdbserver/.. -I../../../binutils-gdb/gdb/gdbserver/../../include -I../../../binutils-gdb/gdb/gdbserver/../gnulib/import -Ibuild-gnulib-gdbserver/import  -Wall -Wpointer-arith -Wno-unused -Wunused-value -Wunused-function -Wno-switch -Wno-char-subscripts -Wempty-body -Wunused-but-set-parameter -Wunused-but-set-variable -Wno-sign-compare -Wno-narrowing -Wno-error=maybe-uninitialized -Wno-format -Werror -DGDBSERVER -c -o win32-low.o -MT win32-low.o -MMD -MP -MF .deps/win32-low.Tpo ../../../binutils-gdb/gdb/gdbserver/win32-low.c
 ../../../binutils-gdb/gdb/gdbserver/win32-low.c: In function 'BOOL create_process(const char*, char*, DWORD, PROCESS_INFORMATION*)':
 ../../../binutils-gdb/gdb/gdbserver/win32-low.c:566:48: error: 'get_inferior_cwd' was not declared in this scope
    const char *inferior_cwd = get_inferior_cwd ();
						 ^
 make[4]: *** [win32-low.o] Error 1
It can be fixed by simply including the right header file.
gdb/gdbserver/ChangeLog:
2017-10-06  Yuanhui Zhang  <asmwarrior@gmail.com>
	* win32-low.c: Include "common-inferior.h".
+2017-10-06  Yuanhui Zhang  <asmwarrior@gmail.com>
+
+       * win32-low.c: Include "common-inferior.h".
+
 2017-10-04  Sergio Durigan Junior  <sergiodj@redhat.com>
 
        * inferiors.c (set_inferior_cwd): New function.
 
 #include <psapi.h>
 #include <process.h>
 #include "gdb_tilde_expand.h"
+#include "common-inferior.h"
 
 #ifndef USE_WIN32API
 #include <sys/cygwin.h>