diff --git a/meson.build b/meson.build
index 74b10d1a0c..e6e6883bad 100644
--- a/meson.build
+++ b/meson.build
@@ -1086,10 +1086,6 @@ if compiler.has_header('alloca.h')
   libgit_c_args += '-DHAVE_ALLOCA_H'
 endif
 
-if compiler.has_header('sys/sysinfo.h')
-  libgit_c_args += '-DHAVE_SYSINFO'
-endif
-
 # Windows has libgen.h and a basename implementation, but we still need our own
 # implementation to threat things like drive prefixes specially.
 if host_machine.system() == 'windows' or not compiler.has_header('libgen.h')
@@ -1112,18 +1108,22 @@ if host_machine.system() == 'windows'
     networking_dependencies += winsock
   endif
 else
-  libresolv = compiler.find_library('resolv', required: false)
-  if libresolv.found()
-    networking_dependencies += libresolv
-  endif
+  networking_dependencies += [
+    compiler.find_library('nsl', required: false),
+    compiler.find_library('resolv', required: false),
+    compiler.find_library('socket', required: false),
+  ]
 endif
 libgit_dependencies += networking_dependencies
 
-foreach symbol : ['inet_ntop', 'inet_pton', 'strerror']
-  if not compiler.has_function(symbol, dependencies: networking_dependencies)
-    libgit_c_args += '-DNO_' + symbol.to_upper()
-  endif
-endforeach
+if host_machine.system() != 'windows'
+  foreach symbol : ['inet_ntop', 'inet_pton', 'hstrerror']
+    if not compiler.has_function(symbol, dependencies: networking_dependencies)
+      libgit_c_args += '-DNO_' + symbol.to_upper()
+      libgit_sources += 'compat/' + symbol + '.c'
+    endif
+  endforeach
+endif
 
 has_ipv6 = compiler.has_function('getaddrinfo', dependencies: networking_dependencies)
 if not has_ipv6
@@ -1161,11 +1161,6 @@ else
   build_options_config.set('NO_UNIX_SOCKETS', '1')
 endif
 
-if not compiler.has_function('pread')
-  libgit_c_args += '-DNO_PREAD'
-  libgit_sources += 'compat/pread.c'
-endif
-
 if host_machine.system() == 'darwin'
   libgit_sources += 'compat/precompose_utf8.c'
   libgit_c_args += '-DPRECOMPOSE_UNICODE'
@@ -1300,6 +1295,10 @@ if host_machine.system() != 'windows'
   endif
 endif
 
+if compiler.has_member('struct sysinfo', 'totalram', prefix: '#include <sys/sysinfo.h>')
+  libgit_c_args += '-DHAVE_SYSINFO'
+endif
+
 if compiler.has_member('struct stat', 'st_mtimespec.tv_nsec', prefix: '#include <sys/stat.h>')
   libgit_c_args += '-DUSE_ST_TIMESPEC'
 elif not compiler.has_member('struct stat', 'st_mtim.tv_nsec', prefix: '#include <sys/stat.h>')
@@ -1318,77 +1317,57 @@ if not compiler.has_member('struct passwd', 'pw_gecos', prefix: '#include <pwd.h
   libgit_c_args += '-DNO_GECOS_IN_PWENT'
 endif
 
+checkfuncs = {
+  'strcasestr' : ['strcasestr.c'],
+  'memmem' : ['memmem.c'],
+  'strlcpy' : ['strlcpy.c'],
+  'strtoull' : [],
+  'setenv' : ['setenv.c'],
+  'mkdtemp' : ['mkdtemp.c'],
+  'initgroups' : [],
+  'strtoumax' : ['strtoumax.c', 'strtoimax.c'],
+  'pread' : ['pread.c'],
+}
+
+if host_machine.system() == 'windows'
+  libgit_c_args += '-DUSE_WIN32_MMAP'
+else
+  checkfuncs += {
+    'mmap' : ['mmap.c'],
+    # provided by compat/mingw.c.
+    'unsetenv' : ['unsetenv.c'],
+    # provided by compat/mingw.c.
+    'getpagesize' : [],
+  }
+endif
+
+foreach func, impls : checkfuncs
+  if not compiler.has_function(func)
+    libgit_c_args += '-DNO_' + func.to_upper()
+    foreach impl : impls
+      libgit_sources += 'compat/' + impl
+    endforeach
+  endif
+endforeach
+
 if compiler.has_function('sync_file_range')
   libgit_c_args += '-DHAVE_SYNC_FILE_RANGE'
 endif
 
-if not compiler.has_function('strcasestr')
-  libgit_c_args += '-DNO_STRCASESTR'
-  libgit_sources += 'compat/strcasestr.c'
-endif
-
-if not compiler.has_function('memmem')
-  libgit_c_args += '-DNO_MEMMEM'
-  libgit_sources += 'compat/memmem.c'
-endif
-
-if not compiler.has_function('strlcpy')
-  libgit_c_args += '-DNO_STRLCPY'
-  libgit_sources += 'compat/strlcpy.c'
-endif
-
 if not compiler.has_function('strdup')
   libgit_c_args += '-DOVERRIDE_STRDUP'
   libgit_sources += 'compat/strdup.c'
 endif
 
-if not compiler.has_function('strtoumax')
-  libgit_c_args += '-DNO_STRTOUMAX'
-  libgit_sources += [
-    'compat/strtoumax.c',
-    'compat/strtoimax.c',
-  ]
-endif
-
-if not compiler.has_function('strtoull')
-  libgit_c_args += '-DNO_STRTOULL'
-endif
-
-if not compiler.has_function('setenv')
-  libgit_c_args += '-DNO_SETENV'
-  libgit_sources += 'compat/setenv.c'
-endif
-
 if not compiler.has_function('qsort')
   libgit_c_args += '-DINTERNAL_QSORT'
 endif
 libgit_sources += 'compat/qsort_s.c'
 
-# unsetenv is provided by compat/mingw.c.
-if host_machine.system() != 'windows' and not compiler.has_function('unsetenv')
-  libgit_c_args += '-DNO_UNSETENV'
-  libgit_sources += 'compat/unsetenv.c'
-endif
-
-if not compiler.has_function('mkdtemp')
-  libgit_c_args += '-DNO_MKDTEMP'
-  libgit_sources += 'compat/mkdtemp.c'
-endif
-
-if not compiler.has_function('initgroups')
-  libgit_c_args += '-DNO_INITGROUPS'
-endif
-
 if compiler.has_function('getdelim')
   libgit_c_args += '-DHAVE_GETDELIM'
 endif
 
-if host_machine.system() == 'windows'
-  libgit_c_args += '-DUSE_WIN32_MMAP'
-elif not compiler.has_function('mmap')
-  libgit_c_args += '-DNO_MMAP'
-  libgit_sources += 'compat/mmap.c'
-endif
 
 if compiler.has_function('clock_gettime')
   libgit_c_args += '-DHAVE_CLOCK_GETTIME'