Add configure host detection to set standards flags correctly.

Linux and MacOS were tolerant of having all standards flags set but BSD was not.

Instead detect the host type and set standards flags as appropriate.

doc/xml/release.xml

@@ -27,6 +27,15 @@
                 </release-feature-list>
 
                 <release-improvement-list>
+                    <release-item>
+                        <release-item-contributor-list>
+                             <release-item-contributor id="marc.cousin"/>
+                             <release-item-reviewer id="david.steele"/>
+                        </release-item-contributor-list>
+
+                        <p>Add configure host detection to set standards flags correctly.</p>
+                    </release-item>
+
                     <release-item>
                         <release-item-contributor-list>
                              <release-item-reviewer id="cynthia.shang"/>

src/Makefile.in

@@ -8,7 +8,7 @@
 CC = @CC@
 
 # Standards
-CSTANDARD = -std=c99 -D_POSIX_C_SOURCE=200809L -D_DARWIN_C_SOURCE
+CSTANDARD = @CSTANDARD@
 
 # Optimizations
 COPTIMIZE = @COPTIMIZE@

src/build/configure.ac

@@ -9,6 +9,21 @@ AC_CONFIG_AUX_DIR(build)
 # ----------------------------------------------------------------------------------------------------------------------------------
 AC_PROG_CC_C99
 
+# Build C standard based on the host type.  C99 is required and other flags are added depending on the host.
+# ----------------------------------------------------------------------------------------------------------------------------------
+AC_CANONICAL_HOST
+CSTANDARD="-std=c99"
+
+case $host_os in
+    darwin*)
+        AC_SUBST(CSTANDARD, "${CSTANDARD?} -D_DARWIN_C_SOURCE")
+        ;;
+
+    linux*)
+        AC_SUBST(CSTANDARD, "${CSTANDARD?} -D_POSIX_C_SOURCE=200809L")
+        ;;
+esac
+
 # Set warnings and optimizations based on build type (i.e. production or test)
 # ----------------------------------------------------------------------------------------------------------------------------------
 warning='-Wall -Wextra -Wno-clobbered -Wno-missing-field-initializers'

src/configure

@@ -630,6 +630,15 @@ CINCLUDE
 CWARNING
 COPTIMIZE_PAGE_CHECKSUM
 COPTIMIZE
+CSTANDARD
+host_os
+host_vendor
+host_cpu
+host
+build_os
+build_vendor
+build_cpu
+build
 OBJEXT
 EXEEXT
 ac_ct_CC
@@ -1299,6 +1308,10 @@ Fine tuning of the installation directories:
 _ACEOF
 
   cat <<\_ACEOF
+
+System types:
+  --build=BUILD     configure for building on BUILD [guessed]
+  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
 _ACEOF
 fi
 
@@ -3039,6 +3052,93 @@ fi
 
 
 
+# Build C standard based on the host type.  C99 is required and other flags are added depending on the host.
+# ----------------------------------------------------------------------------------------------------------------------------------
+# Make sure we can run config.sub.
+$SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
+  as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
+$as_echo_n "checking build system type... " >&6; }
+if ${ac_cv_build+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_build_alias=$build_alias
+test "x$ac_build_alias" = x &&
+  ac_build_alias=`$SHELL "$ac_aux_dir/config.guess"`
+test "x$ac_build_alias" = x &&
+  as_fn_error $? "cannot guess build type; you must specify one" "$LINENO" 5
+ac_cv_build=`$SHELL "$ac_aux_dir/config.sub" $ac_build_alias` ||
+  as_fn_error $? "$SHELL $ac_aux_dir/config.sub $ac_build_alias failed" "$LINENO" 5
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
+$as_echo "$ac_cv_build" >&6; }
+case $ac_cv_build in
+*-*-*) ;;
+*) as_fn_error $? "invalid value of canonical build" "$LINENO" 5;;
+esac
+build=$ac_cv_build
+ac_save_IFS=$IFS; IFS='-'
+set x $ac_cv_build
+shift
+build_cpu=$1
+build_vendor=$2
+shift; shift
+# Remember, the first character of IFS is used to create $*,
+# except with old shells:
+build_os=$*
+IFS=$ac_save_IFS
+case $build_os in *\ *) build_os=`echo "$build_os" | sed 's/ /-/g'`;; esac
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
+$as_echo_n "checking host system type... " >&6; }
+if ${ac_cv_host+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test "x$host_alias" = x; then
+  ac_cv_host=$ac_cv_build
+else
+  ac_cv_host=`$SHELL "$ac_aux_dir/config.sub" $host_alias` ||
+    as_fn_error $? "$SHELL $ac_aux_dir/config.sub $host_alias failed" "$LINENO" 5
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
+$as_echo "$ac_cv_host" >&6; }
+case $ac_cv_host in
+*-*-*) ;;
+*) as_fn_error $? "invalid value of canonical host" "$LINENO" 5;;
+esac
+host=$ac_cv_host
+ac_save_IFS=$IFS; IFS='-'
+set x $ac_cv_host
+shift
+host_cpu=$1
+host_vendor=$2
+shift; shift
+# Remember, the first character of IFS is used to create $*,
+# except with old shells:
+host_os=$*
+IFS=$ac_save_IFS
+case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
+
+
+CSTANDARD="-std=c99"
+
+case $host_os in
+    darwin*)
+        CSTANDARD="${CSTANDARD?} -D_DARWIN_C_SOURCE"
+
+        ;;
+
+    linux*)
+        CSTANDARD="${CSTANDARD?} -D_POSIX_C_SOURCE=200809L"
+
+        ;;
+esac
+
 # Set warnings and optimizations based on build type (i.e. production or test)
 # ----------------------------------------------------------------------------------------------------------------------------------
 warning='-Wall -Wextra -Wno-clobbered -Wno-missing-field-initializers'