configure: fix: _TIME_BITS is tied to _FILE_OFFSET_BITS

This problem was reported by Void Linux package maintainer
adigitoleo.

* configure: in glibc, _TIME_BITS and _FILE_OFFSET_BITS
are not independent. You cannot make the former 64 if
the latter isn't. I'm rewriting the test to check for
these together, in all combinations. We succeed if
we detect a combination that makes both time_t and
off_t 64 bits. If we don't find such a combination then
we at least enable 64 bit off_t alone or 64 bit time_t
alone, if we encountered an option which does that.

1 files changed, 69 insertions, 29 deletions

diff --git a/configure b/configure
index 823fad0a..720bcd77 100755
--- a/configure
+++ b/configure
@@ -3566,10 +3566,16 @@ fi
 
 printf "Checking how to enable 64 bit off_t and time_t ..."
 
+file_offset_only_define=none
+time_bits_only_define=none
 file_offset_define=none
 time_bits_define=none
 
-for try in NOTHING _LARGE_FILES=1 _FILE_OFFSET_BITS=64 _TIME_BITS=64; do
+# We have a nested loop over pairs of options for off_t and time_t
+# because in Glibc, they are not independent. _TIME_BITS=64 cannot
+# be enabled if _FILE_OFFSET_BITS=64 isn't.
+for try_f in NOTHING _LARGE_FILES=1 _FILE_OFFSET_BITS=64; do
+  for try_t in NOTHING _TIME_BITS=64; do
   cat > conftest.c <<!
 #include <limits.h>
 #include <time.h>
@@ -3591,48 +3597,80 @@ struct sizes {
   "\nSIZEOF_TIME_T=", DEC(sizeof (time_t)),
   "\n"
 };
-
 !
-  if ! conftest_o EXTRA_FLAGS=-D$try ; then
-    printf "failed\n\n"
+    if ! conftest_o EXTRA_FLAGS="-D$try_f -D$try_t" ; then
+      continue
+    fi
 
-    printf "Errors from compilation: \n\n"
-    cat conftest.err
-    exit 1
-  fi
+    eval $(tr '\0' ' ' < conftest.o  | grep SIZEOF | sed -e 's/  *//')
 
-  eval $(tr '\0' ' ' < conftest.o  | grep SIZEOF | sed -e 's/  *//')
+    if [ $SIZEOF_OFF_T -eq 0 -o $SIZEOF_BYTE -eq 0 ] ; then
+      printf "failed\n"
+      exit 1
+    fi
 
-  if [ $SIZEOF_OFF_T -eq 0 -o $SIZEOF_BYTE -eq 0 ] ; then
-    printf "failed\n"
-    exit 1
-  fi
+    # Regardless of what happens with time_t, if we detect the
+    # enabling of 64 bit off_t, we record then in the
+    # file_offset_only_define variable, and keep going.
+
+    if [ "$file_offset_only_define" = none ] ; then
+      if [ $(( SIZEOF_BYTE * SIZEOF_OFF_T )) -eq 64 ] ; then
+        if [ $try_f = NOTHING ] ; then
+          file_offset_only_define=
+        else
+          file_offset_only_define=$try_f
+        fi
+      fi
+    fi
 
-  if [ "$file_offset_define" = none ] ; then
-    if [ $(( SIZEOF_BYTE * SIZEOF_OFF_T )) -eq 64 ] ; then
-      if [ $try = NOTHING ] ; then
-        file_offset_define=
-      else
-        printf -- " -D%s" $try
-        file_offset_define=$try
+    # Regardless of what happens with off_t, if we detect the
+    # enabling of 64 bit time_t, we record then in the
+    # time_bits_only_define variable, and keep going.
+
+    if [ "$time_bits_only_define" = none ] ; then
+      if [ $(( SIZEOF_BYTE * SIZEOF_TIME_T )) -eq 64 ] ; then
+        if [ $try_t = NOTHING ] ; then
+          time_bits_only_define=
+        else
+          time_bits_only_define=$try_t
+        fi
       fi
     fi
-  fi
 
-  if [ "$time_bits_define" = none ] ; then
-    if [ $(( SIZEOF_BYTE * SIZEOF_TIME_T )) -eq 64 ] ; then
-      if [ $try = NOTHING ] ; then
+    # If we get a combination of options (or lack thereof) that results in
+    # both 64 bit off_t and time_t, then we record those and are done.
+
+    if [ $(( SIZEOF_BYTE * SIZEOF_OFF_T )) -eq 64 ] && \
+       [ $(( SIZEOF_BYTE * SIZEOF_TIME_T )) -eq 64 ]
+    then
+      if [ $try_f = NOTHING ] ; then
+        file_offset_define=
+      else
+        file_offset_define=$try_f
+      fi
+      if [ $try_t = NOTHING ] ; then
         time_bits_define=
       else
-        printf -- " -D%s" $try
-        time_bits_define=$try
+        time_bits_define=$try_t
       fi
-    fi
-  fi
 
-  [ "$file_offset_define" = none -o "$time_bits_define" = none ] || break
+      break
+    fi
+  done
 done
 
+# If 64 bit time_t was not detected, here we check whether we did
+# detect 64 bit off_t in above loop; and copy that auxiliary variable.
+if [ "$time_bits_define" = none -a -n "$file_offset_only_define" ] ; then
+  file_offset_define=$file_offset_only_define
+fi
+
+# Vice versa, if 64 bit off_t was not detected, here we check whether we did
+# detect 64 bit time_t in above loop; and copy that auxiliary variable.
+if [ "$file_offset_define" = none -a -n "$time_bits_only_define" ] ; then
+  time_bits_define=$time_bits_only_define
+fi
+
 case "$time_bits_define" in
 none )
   if [ "$big_time" ] ; then
@@ -3663,6 +3701,7 @@ esac
 if [ "$file_offset_define" = none ] ; then
   printf " (no 64 bit off_t)"
 elif [ -n "$file_offset_define" ] ; then
+  printf -- " -D%s" "$file_offset_define"
   printf "#define CONFIG_LARGE_FILE_OFFSET 1\n" >> config.h
   lang_flags="$lang_flags -D$file_offset_define"
 fi
@@ -3670,6 +3709,7 @@ fi
 if [ "$time_bits_define" = none ] ; then
   printf " (no 64 bit time_t)"
 elif [ -n "$time_bits_define" ] ; then
+  printf -- " -D%s" "$time_bits_define"
   lang_flags="$lang_flags -D$time_bits_define"
 fi