build: get rid of `HAVE_TIME_H`

As advertized by `autoreconf`:

> All current systems provide time.h; it need not be checked for.

Hence, remove the check for it in `configure.ac` and remove conditional
inclusion of the header in `HAVE_TIME_H` blocks where applicable.

The `time.h` header was being included in various source files without a
`HAVE_TIME_H` guard already anyway.

9 files changed, 4 insertions, 20 deletions

diff --git a/configure.ac b/configure.ac
index 5f0a812e48..0f8e0ba4b4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -845,7 +845,7 @@ dnl    off_t, because it will affect the result of that test.
 AC_SYS_LARGEFILE
 
 dnl ** check for specific header (.h) files that we are interested in
-AC_CHECK_HEADERS([ctype.h dirent.h dlfcn.h errno.h fcntl.h grp.h limits.h locale.h nlist.h pthread.h pwd.h signal.h sys/param.h sys/mman.h sys/resource.h sys/select.h sys/time.h sys/timeb.h sys/timerfd.h sys/timers.h sys/times.h sys/utsname.h sys/wait.h termios.h time.h utime.h windows.h winsock.h sched.h])
+AC_CHECK_HEADERS([ctype.h dirent.h dlfcn.h errno.h fcntl.h grp.h limits.h locale.h nlist.h pthread.h pwd.h signal.h sys/param.h sys/mman.h sys/resource.h sys/select.h sys/time.h sys/timeb.h sys/timerfd.h sys/timers.h sys/times.h sys/utsname.h sys/wait.h termios.h utime.h windows.h winsock.h sched.h])
 
 dnl sys/cpuset.h needs sys/param.h to be included first on FreeBSD 9.1; #7708
 AC_CHECK_HEADERS([sys/cpuset.h], [], [],
diff --git a/libraries/base/System/CPUTime/Posix/ClockGetTime.hsc b/libraries/base/System/CPUTime/Posix/ClockGetTime.hsc
index f24dec3b14..259cee8226 100644
--- a/libraries/base/System/CPUTime/Posix/ClockGetTime.hsc
+++ b/libraries/base/System/CPUTime/Posix/ClockGetTime.hsc
@@ -2,10 +2,8 @@
 
 #include "HsFFI.h"
 #include "HsBaseConfig.h"
-#if HAVE_TIME_H
 #include <unistd.h>
 #include <time.h>
-#endif
 
 module System.CPUTime.Posix.ClockGetTime
     ( getCPUTime
diff --git a/libraries/base/aclocal.m4 b/libraries/base/aclocal.m4
index 083a427fc7..da1ee301ec 100644
--- a/libraries/base/aclocal.m4
+++ b/libraries/base/aclocal.m4
@@ -78,9 +78,7 @@ AC_DEFUN([FPTOOLS_HTYPE_INCLUDES],
 # include <signal.h>
 #endif
 
-#if HAVE_TIME_H
-# include <time.h>
-#endif
+#include <time.h>
 
 #if HAVE_TERMIOS_H
 # include <termios.h>
diff --git a/libraries/base/cbits/sysconf.c b/libraries/base/cbits/sysconf.c
index bbf785326a..1bce685296 100644
--- a/libraries/base/cbits/sysconf.c
+++ b/libraries/base/cbits/sysconf.c
@@ -6,9 +6,7 @@
 #endif
 
 /* for CLK_TCK */
-#if HAVE_TIME_H
 #include <time.h>
-#endif
 
 long clk_tck(void) {
 #if defined(CLK_TCK)
diff --git a/libraries/base/include/HsBase.h b/libraries/base/include/HsBase.h
index 1880f28d86..d55ec0747a 100644
--- a/libraries/base/include/HsBase.h
+++ b/libraries/base/include/HsBase.h
@@ -74,9 +74,7 @@
 #  include <sys/timers.h>
 # endif
 #endif
-#if HAVE_TIME_H
 #include <time.h>
-#endif
 #if HAVE_SYS_TIMEB_H && !defined(__FreeBSD__)
 #include <sys/timeb.h>
 #endif
diff --git a/m4/fp_check_timer_create.m4 b/m4/fp_check_timer_create.m4
index e698885065..957772ba45 100644
--- a/m4/fp_check_timer_create.m4
+++ b/m4/fp_check_timer_create.m4
@@ -20,9 +20,7 @@ then
 #if defined(HAVE_STDLIB_H)
 #include <stdlib.h>
 #endif
-#if defined(HAVE_TIME_H)
 #include <time.h>
-#endif
 #if defined(HAVE_SIGNAL_H)
 #include <signal.h>
 #endif
diff --git a/rts/RtsUtils.c b/rts/RtsUtils.c
index 3878a40697..2017884e48 100644
--- a/rts/RtsUtils.c
+++ b/rts/RtsUtils.c
@@ -15,9 +15,7 @@
 #include "Schedule.h"
 #include "RtsFlags.h"
 
-#if defined(HAVE_TIME_H)
 #include <time.h>
-#endif
 
 /* HACK: On Mac OS X 10.4 (at least), time.h doesn't declare ctime_r with
  *       _POSIX_C_SOURCE. If this is the case, we declare it ourselves.
diff --git a/rts/posix/Clock.h b/rts/posix/Clock.h
index 92d0581877..2476454c3e 100644
--- a/rts/posix/Clock.h
+++ b/rts/posix/Clock.h
@@ -12,9 +12,7 @@
 # include <unistd.h>
 #endif
 
-#if defined(HAVE_TIME_H)
-# include <time.h>
-#endif
+#include <time.h>
 
 #if defined(HAVE_SYS_TIME_H)
 # include <sys/time.h>
diff --git a/rts/win32/GetTime.c b/rts/win32/GetTime.c
index e0f5e7d406..1722e14f8f 100644
--- a/rts/win32/GetTime.c
+++ b/rts/win32/GetTime.c
@@ -11,9 +11,7 @@
 
 #include <windows.h>
 
-#if defined(HAVE_TIME_H)
-# include <time.h>
-#endif
+#include <time.h>
 
 /* Convert FILETIMEs into secs */