diff --git a/cmake/ConfigureChecks.cmake b/cmake/ConfigureChecks.cmake
index 4eb8e64fc..6e1168e73 100644
--- a/cmake/ConfigureChecks.cmake
+++ b/cmake/ConfigureChecks.cmake
@@ -17,38 +17,38 @@ ENDIF()
 # Set up the config.h file.
 SET(PACKAGE_NAME "fish")
 SET(PACKAGE_TARNAME "fish")
-INCLUDE(CheckFunctionExists)
 INCLUDE(CheckCXXSymbolExists)
 INCLUDE(CheckIncludeFileCXX)
 INCLUDE(CheckIncludeFiles)
 INCLUDE(CheckStructHasMember)
 INCLUDE(CheckCXXSourceCompiles)
 INCLUDE(CheckTypeSize)
-CHECK_FUNCTION_EXISTS(backtrace_symbols HAVE_BACKTRACE_SYMBOLS)
-CHECK_FUNCTION_EXISTS(clock_gettime HAVE_CLOCK_GETTIME)
-CHECK_FUNCTION_EXISTS(ctermid_r HAVE_CTERMID_R)
+CHECK_CXX_SYMBOL_EXISTS(backtrace_symbols execinfo.h HAVE_BACKTRACE_SYMBOLS)
+CHECK_CXX_SYMBOL_EXISTS(clock_gettime time.h HAVE_CLOCK_GETTIME)
+CHECK_CXX_SYMBOL_EXISTS(ctermid_r stdio.h HAVE_CTERMID_R)
 CHECK_STRUCT_HAS_MEMBER("struct dirent" d_type dirent.h HAVE_STRUCT_DIRENT_D_TYPE LANGUAGE CXX)
-CHECK_FUNCTION_EXISTS(dirfd HAVE_DIRFD)
+CHECK_CXX_SYMBOL_EXISTS(dirfd "sys/types.h;dirent.h" HAVE_DIRFD)
 CHECK_INCLUDE_FILE_CXX(execinfo.h HAVE_EXECINFO_H)
-CHECK_FUNCTION_EXISTS(flock HAVE_FLOCK)
+CHECK_CXX_SYMBOL_EXISTS(flock sys/file.h HAVE_FLOCK)
 # futimens is new in OS X 10.13 but is a weak symbol.
 # Don't assume it exists just because we can link - it may be null.
 CHECK_CXX_SYMBOL_EXISTS(futimens sys/stat.h HAVE_FUTIMENS)
-CHECK_FUNCTION_EXISTS(futimes HAVE_FUTIMES)
-CHECK_FUNCTION_EXISTS(getifaddrs HAVE_GETIFADDRS)
-CHECK_FUNCTION_EXISTS(getpwent HAVE_GETPWENT)
-CHECK_FUNCTION_EXISTS(gettext HAVE_GETTEXT)
-CHECK_FUNCTION_EXISTS(killpg HAVE_KILLPG)
-CHECK_FUNCTION_EXISTS(lrand48_r HAVE_LRAND48_R)
-CHECK_FUNCTION_EXISTS(mkostemp HAVE_MKOSTEMP)
+CHECK_CXX_SYMBOL_EXISTS(futimes sys/time.h HAVE_FUTIMES)
+CHECK_CXX_SYMBOL_EXISTS(getifaddrs ifaddrs.h HAVE_GETIFADDRS)
+CHECK_CXX_SYMBOL_EXISTS(getpwent pwd.h HAVE_GETPWENT)
+CHECK_CXX_SYMBOL_EXISTS(gettext libintl.h HAVE_GETTEXT)
+CHECK_CXX_SYMBOL_EXISTS(killpg "sys/types.h;signal.h" HAVE_KILLPG)
+CHECK_CXX_SYMBOL_EXISTS(lrand48_r stdlib.h HAVE_LRAND48_R)
+# mkostemp is in stdlib in glibc and FreeBSD, but unistd on macOS
+CHECK_CXX_SYMBOL_EXISTS(mkostemp "stdlib.h;unistd.h" HAVE_MKOSTEMP)
 SET(HAVE_NCURSES_CURSES_H ${CURSES_HAVE_NCURSES_CURSES_H})
 SET(HAVE_NCURSES_H ${CURSES_HAVE_NCURSES_H})
 CHECK_INCLUDE_FILE_CXX("ncurses/term.h" HAVE_NCURSES_TERM_H)
 CHECK_INCLUDE_FILE_CXX(siginfo.h HAVE_SIGINFO_H)
 CHECK_INCLUDE_FILE_CXX(spawn.h HAVE_SPAWN_H)
-CHECK_FUNCTION_EXISTS(std::wcscasecmp HAVE_STD__WCSCASECMP)
-CHECK_FUNCTION_EXISTS(std::wcsdup HAVE_STD__WCSDUP)
-CHECK_FUNCTION_EXISTS(std::wcsncasecmp HAVE_STD__WCSNCASECMP)
+CHECK_CXX_SYMBOL_EXISTS(std::wcscasecmp wchar.h HAVE_STD__WCSCASECMP)
+CHECK_CXX_SYMBOL_EXISTS(std::wcsdup wchar.h HAVE_STD__WCSDUP)
+CHECK_CXX_SYMBOL_EXISTS(std::wcsncasecmp wchar.h HAVE_STD__WCSNCASECMP)
 CHECK_STRUCT_HAS_MEMBER("struct stat" st_ctime_nsec "sys/stat.h" HAVE_STRUCT_STAT_ST_CTIME_NSEC
     LANGUAGE CXX)
 CHECK_STRUCT_HAS_MEMBER("struct stat" st_mtimespec.tv_nsec "sys/stat.h"
@@ -61,11 +61,11 @@ CHECK_INCLUDE_FILE_CXX(sys/select.h HAVE_SYS_SELECT_H)
 CHECK_INCLUDE_FILES("sys/types.h;sys/sysctl.h" HAVE_SYS_SYSCTL_H)
 CHECK_INCLUDE_FILE_CXX(termios.h HAVE_TERMIOS_H) # Needed for TIOCGWINSZ
 CHECK_INCLUDE_FILE_CXX(term.h HAVE_TERM_H)
-CHECK_FUNCTION_EXISTS(wcscasecmp HAVE_WCSCASECMP)
-CHECK_FUNCTION_EXISTS(wcsdup HAVE_WCSDUP)
-CHECK_FUNCTION_EXISTS(wcslcpy HAVE_WCSLCPY)
-CHECK_FUNCTION_EXISTS(wcsncasecmp HAVE_WCSNCASECMP)
-CHECK_FUNCTION_EXISTS(wcsndup HAVE_WCSNDUP)
+CHECK_CXX_SYMBOL_EXISTS(wcscasecmp wchar.h HAVE_WCSCASECMP)
+CHECK_CXX_SYMBOL_EXISTS(wcsdup wchar.h HAVE_WCSDUP)
+CHECK_CXX_SYMBOL_EXISTS(wcslcpy wchar.h HAVE_WCSLCPY)
+CHECK_CXX_SYMBOL_EXISTS(wcsncasecmp wchar.h HAVE_WCSNCASECMP)
+CHECK_CXX_SYMBOL_EXISTS(wcsndup wchar.h HAVE_WCSNDUP)
 
 CHECK_CXX_SYMBOL_EXISTS(_sys_errs stdlib.h HAVE__SYS__ERRS)