configure: memalign fixes.

This fixes build problems on Mac OS and Solaris due
to the introduction of the use of memalign.

* configure: After detecting that __EXTENSIONS__ is
required on Solaris and adding that to lang_flags, we
must call gen_config_make so that it becomes available to
subsequent configure tests. On Solaris, memalign is just in
<stdlib.h>, so let's test for that first, then test for a
memalign in <malloc.h>, and in that case add HAVE_MALLOC_H
into config.h. Also, fixing two bugs here. Firstly, the
memalign test used inverted logic, causing HAVE_MEMALIGN
to be defined on platforms that don't have it. Secondly,
the dummy while loop that is just supposed to be a control
structure for forward breaks turned infinite due to a
missing break at the bottom.

* lib.c: if HAVE_MALLOC_H is defined and nonzero, then
include <malloc.h>.

2 files changed, 24 insertions, 2 deletions

diff --git a/configure b/configure
index 34be9b59..5659e14f 100755
--- a/configure
+++ b/configure
@@ -2482,6 +2482,7 @@ elif conftest EXTRA_FLAGS=-D__EXTENSIONS__=1 ; then
   printf "yes\n"
   printf "#define HAVE_SETGROUPS 1\n" >> config.h
   lang_flags="$lang_flags -D__EXTENSIONS__=1" # Solaris buggery
+  gen_config_make
   have_unistd=y
   have_sys_types=y
 else
@@ -2679,6 +2680,25 @@ printf "Checking for malloc-with-alignment function ... "
 
 while true ; do
   cat > conftest.c <<!
+#include <stdlib.h>
+
+int main(void)
+{
+  void *bytes = memalign(16, 42);
+  return 0;
+}
+!
+
+  if conftest ; then
+    printf "memalign\n"
+    printf "#define HAVE_MEMALIGN 1\n" $try_header >> config.h
+    break;
+  fi
+
+  cat conftest.err
+  exit 1
+
+  cat > conftest.c <<!
 #include <malloc.h>
 
 int main(void)
@@ -2688,9 +2708,10 @@ int main(void)
 }
 !
 
-  if ! conftest ; then
+  if conftest ; then
     printf "memalign\n"
     printf "#define HAVE_MEMALIGN 1\n" $try_header >> config.h
+    printf "#define HAVE_MALLOC_H 1\n" $try_header >> config.h
     break;
   fi
 
@@ -2711,6 +2732,7 @@ int main(void)
   fi
 
   printf "none\n"
+  break
 done
 
 printf "Checking for termios ... "
diff --git a/lib.c b/lib.c
index be0622cb..304bee3a 100644
--- a/lib.c
+++ b/lib.c
@@ -45,7 +45,7 @@
 #define NOMINMAX
 #include <windows.h>
 #endif
-#if HAVE_MEMALIGN
+#if HAVE_MALLOC_H
 #include <malloc.h>
 #endif
 #include "lib.h"