Fixed many units to make compiling with GCC flag -Werror possible.

Replaced exit() with return in main() due to missing #include <stdlib.h>.
Added "(void) variable;" to silence warning about unused variable.
Fixed Csym for GCC again (see FIXME tag).
Added FIXME regarding VAL_EAGAIN.
Added #define _GNU_SOURCE for pread() and pwrite() to get prototypes on GLIBC.
Removed blunt cc output redirections because you can't fix what you can't see.


git-svn-id: svn://svn.code.sf.net/p/dist/code/trunk/dist@79 2592e710-e01b-42a5-8df0-11608a6cc53d

18 files changed, 80 insertions, 43 deletions

diff --git a/mcon/U/Csym.U b/mcon/U/Csym.U
index e7c7c4b..ff944ea 100644
--- a/mcon/U/Csym.U
+++ b/mcon/U/Csym.U
@@ -79,9 +79,19 @@ yes)
 ?X:
 ?X: Lastly, gcc 3.4 otimizes &missing == 0 away, so we use + 2 instead now.
 ?X: The GNU folks like to do weird things, don't they? -- RAM, 2004-06-05
+?X
+?X: The above was invalid because main returns an int not a pointer.
+?X: Using != or == does not work because GCC complains the pointer will
+?X: never be NULL if the function exists. It is a warning meant to prevent
+?X: using an address of a function by accident instead of calling it.
+?X: However, &missing > 0 is indeed silently optimized away.
+?X
+?X: FIXME: There must be a test whether non-existing functions are found!
 ?X:
-		echo "extern char $1$tdc; int main() { return &$1$tc + 2; }" > t.c;
-		if $cc $ccflags $ldflags -o t t.c $libs >/dev/null 2>&1;
+?X:. -- cbiere, 2011-01-18
+?X:
+		echo "extern char $1$tdc; int main(void) { return (unsigned long) &$1$tc > 2; }" > t.c;
+		if $cc $ccflags $ldflags -o t t.c $libs;
 		then tval=true;
 		else tval=false;
 		fi;
diff --git a/mcon/U/abortsig.U b/mcon/U/abortsig.U
index a13f30f..7723b7e 100644
--- a/mcon/U/abortsig.U
+++ b/mcon/U/abortsig.U
@@ -38,8 +38,9 @@ case "$abortsig" in
 	for signal in SIGIOT SIGILL SIGABRT; do
 		case "$abortsig" in
 		'') $cat >abort.c <<EOP
+/* FIXME: Missing #include <stdlib.h>*/
 #include <signal.h>
-caught() { exit(0); }
+caught() { exit(0); }	/* FIXME: Use _exit() or _Exit() in signal handler  */
 int main()
 {
 #ifdef $signal
diff --git a/mcon/U/byteorder.U b/mcon/U/byteorder.U
index a337080..03665d0 100644
--- a/mcon/U/byteorder.U
+++ b/mcon/U/byteorder.U
@@ -63,7 +63,7 @@ int main()
 	for (i = 0; i < sizeof(long); i++)
 		printf("%c", u.c[i]+'0');
 	printf("\n");
-	exit(0);
+	return 0;
 }
 EOCP
 	xxx_prompt=y
diff --git a/mcon/U/ccflags.U b/mcon/U/ccflags.U
index 876af98..be37f52 100644
--- a/mcon/U/ccflags.U
+++ b/mcon/U/ccflags.U
@@ -373,8 +373,7 @@ and I got the following output:
 
 EOM
 $cat > try.c <<'EOF'
-#include <stdio.h>
-int main() { exit(0); }
+int main() { return 0; }
 EOF
 dflt=y
 ?X: Use "sh -c" to avoid error messages tagged with leading "Configure:".
diff --git a/mcon/U/d_access.U b/mcon/U/d_access.U
index 503ee2a..9834199 100644
--- a/mcon/U/d_access.U
+++ b/mcon/U/d_access.U
@@ -61,8 +61,13 @@ case "$d_access" in
 #ifdef I_UNISTD
 #include <unistd.h>
 #endif
-int main() {
-	exit(R_OK);
+int main(void) {
+	static int mode;
+	mode |= R_OK;
+	mode |= W_OK;
+	mode |= X_OK;
+	mode |= F_OK;
+	return mode ? 0 : 1;
 }
 EOCP
 	: check sys/file.h first, no particular reason here
diff --git a/mcon/U/d_const.U b/mcon/U/d_const.U
index 4801d09..f146b87 100644
--- a/mcon/U/d_const.U
+++ b/mcon/U/d_const.U
@@ -47,13 +47,16 @@ $cat >const.c <<'EOCP'
 ?X: handle typedefs properly if they're declared const. To guard
 ?X: against this, boost up the test by using an explicit typedef...
 typedef struct spug { int drokk; } spug;
-int main()
+int main(void)
 {
-	const char *foo;
-	const spug y;
+	static const char *foo;
+	static const spug y;
+	(void) foo;
+	(void) y;
+	return 0;
 }
 EOCP
-if $cc -c $ccflags const.c >/dev/null 2>&1 ; then
+if $cc -c $ccflags const.c; then
 	val="$define"
 	echo "Yup, it does."
 else
diff --git a/mcon/U/d_memalign.U b/mcon/U/d_memalign.U
index 3adbb69..e814653 100644
--- a/mcon/U/d_memalign.U
+++ b/mcon/U/d_memalign.U
@@ -10,7 +10,7 @@
 ?RCS:
 ?RCS: $Log: d_memalign.U,v $
 ?RCS:
-?MAKE:d_memalign: Trylink cat i_stdlib
+?MAKE:d_memalign: Trylink cat i_stdlib i_malloc
 ?MAKE:	-pick add $@ %<
 ?S:d_memalign:
 ?S:	This variable conditionally defines the HAS_MEMALIGN symbol, which
@@ -25,10 +25,15 @@
 ?LINT:set d_memalign
 : see if memalign exists
 $cat >try.c <<EOC
+#define _GNU_SOURCE
 #$i_stdlib I_STDLIB
 #ifdef I_STDLIB
 #include <stdlib.h>
 #endif
+#$i_malloc I_MALLOC
+#ifdef I_MALLOC
+#include <malloc.h>
+#endif
 int main(void)
 {
 	static size_t align, size;
diff --git a/mcon/U/d_open3.U b/mcon/U/d_open3.U
index 6828112..ee56f45 100644
--- a/mcon/U/d_open3.U
+++ b/mcon/U/d_open3.U
@@ -48,12 +48,12 @@ $cat >open3.c <<'EOCP'
 #ifdef I_SYS_FILE
 #include <sys/file.h>
 #endif
-int main() {
+int main(void) {
 	if(O_RDONLY);
 #ifdef O_TRUNC
-	exit(0);
+	return 0;
 #else
-	exit(1);
+	return 1;
 #endif
 }
 EOCP
diff --git a/mcon/U/d_pread.U b/mcon/U/d_pread.U
index e4f5afd..72edba4 100644
--- a/mcon/U/d_pread.U
+++ b/mcon/U/d_pread.U
@@ -25,6 +25,7 @@
 ?LINT:set d_pread
 : see if pread exists
 $cat >try.c <<EOC
+#define _GNU_SOURCE
 #include <sys/types.h>
 #$i_unistd I_UNISTD
 #ifdef I_UNISTD
diff --git a/mcon/U/d_pwrite.U b/mcon/U/d_pwrite.U
index ed00afc..c568c06 100644
--- a/mcon/U/d_pwrite.U
+++ b/mcon/U/d_pwrite.U
@@ -25,6 +25,7 @@
 ?LINT:set d_pwrite
 : see if pwrite exists
 $cat >try.c <<EOC
+#define _GNU_SOURCE
 #include <sys/types.h>
 #$i_unistd I_UNISTD
 #ifdef I_UNISTD
diff --git a/mcon/U/d_sigsetjmp.U b/mcon/U/d_sigsetjmp.U
index 8a1d474..8ecf709 100644
--- a/mcon/U/d_sigsetjmp.U
+++ b/mcon/U/d_sigsetjmp.U
@@ -65,16 +65,16 @@ case "$d_sigsetjmp" in
 #include <setjmp.h>
 sigjmp_buf env;
 int set = 1;
-int main()
+int main(void)
 {
 	if (sigsetjmp(env,1))
-		exit(set);
+		return set;
 	set = 0;
 	siglongjmp(env, 1);
-	exit(1);
+	return 1;
 }
 EOP
-	if $cc $ccflags $ldflags -o set set.c $libs > /dev/null 2>&1 ; then
+	if $cc $ccflags $ldflags -o set set.c $libs; then
 		if ./set >/dev/null 2>&1; then
 			echo "POSIX sigsetjmp found." >&4
 			val="$define"
diff --git a/mcon/U/d_volatile.U b/mcon/U/d_volatile.U
index f94ca4f..6ef01db 100644
--- a/mcon/U/d_volatile.U
+++ b/mcon/U/d_volatile.U
@@ -41,7 +41,7 @@
 echo " "
 echo 'Checking to see if your C compiler knows about "volatile"...' >&4
 $cat >try.c <<'EOCP'
-int main()
+int main(void)
 {
 ?X:
 ?X: The following seven lines added by Bill Campbell <billc@sierra.com>
@@ -55,13 +55,18 @@ int main()
 		char char_var;
 	};
 	typedef unsigned short foo_t;
-	char *volatile foo;
-	volatile int bar;
-	volatile foo_t blech;
+	static char *volatile foo;
+	static volatile int bar;
+	static volatile foo_t blech;
 	foo = foo;
+	(void) goo;
+	(void) foo;
+	(void) bar;
+	(void) blech;
+	return 0;
 }
 EOCP
-if $cc -c $ccflags try.c >/dev/null 2>&1 ; then
+if $cc -c $ccflags try.c; then
 	val="$define"
 	echo "Yup, it does."
 else
diff --git a/mcon/U/i_time.U b/mcon/U/i_time.U
index cdf1519..c573fa4 100644
--- a/mcon/U/i_time.U
+++ b/mcon/U/i_time.U
@@ -73,7 +73,7 @@ $cat >try.c <<'EOCP'
 #ifdef I_SYSSELECT
 #include <sys/select.h>
 #endif
-int main()
+int main(void)
 {
 	struct tm foo;
 #ifdef S_TIMEVAL
@@ -83,12 +83,12 @@ int main()
 	struct timezone tzp;
 #endif
 	if (foo.tm_sec == foo.tm_sec)
-		exit(0);
+		return 0;
 #ifdef S_TIMEVAL
 	if (bar.tv_sec == bar.tv_sec)
-		exit(0);
+		return 0;
 #endif
-	exit(1);
+	return 1;
 }
 EOCP
 flags=''
diff --git a/mcon/U/i_varhdr.U b/mcon/U/i_varhdr.U
index df6cfe5..e0fd6d1 100644
--- a/mcon/U/i_varhdr.U
+++ b/mcon/U/i_varhdr.U
@@ -109,11 +109,12 @@ va_dcl
 	p = va_arg(ap, char *);
 #endif
 	va_end(ap);
+	return 0;
 }
 EOP
 $cat > varargs <<EOP
 $startsh
-if $cc -c $ccflags -D\$1 varargs.c >/dev/null 2>&1; then
+if $cc -c $ccflags -D\$1 varargs.c; then
 	echo "true"
 else
 	echo "false"
diff --git a/mcon/U/models.U b/mcon/U/models.U
index b903134..52cdd14 100644
--- a/mcon/U/models.U
+++ b/mcon/U/models.U
@@ -64,11 +64,11 @@ case "$models" in
 ?X: We may not use Cppsym or we get a circular dependency through cc.
 ?X: But this should work regardless of which cc we eventually use.
 	$cat >pdp11.c <<'EOP'
-int main() {
+int main(void) {
 #ifdef pdp11
-	exit(0);
+	return 0;
 #else
-	exit(1);
+	return 1;
 #endif
 }
 EOP
diff --git a/mcon/U/nblock_io.U b/mcon/U/nblock_io.U
index 5a5aa04..fef20ac 100644
--- a/mcon/U/nblock_io.U
+++ b/mcon/U/nblock_io.U
@@ -55,6 +55,12 @@
 ?C:VAL_EAGAIN:
 ?C:	This symbol holds the errno error code set by read() when no data was
 ?C:	present on the non-blocking file descriptor.
+?C:
+?C: FIXME: And who guarantees this isn't e.g. device-dependent?
+?C:	   If EAGAIN is defined one should expect it.
+?C:	   If EWOULDBLOCK is defined one should expect it.
+?C:	   If both are defined one should expect both.
+?C: 	   -- cbiere, 2011-01-18
 ?C:.
 ?C:RD_NODATA:
 ?C:	This symbol holds the return code from read() when no data is present
@@ -91,22 +97,22 @@ case "$o_nonblock" in
 '')
 	$cat head.c > try.c
 	$cat >>try.c <<'EOCP'
-int main() {
+#include <stdio.h>
+int main(void) {
 #ifdef O_NONBLOCK
 	printf("O_NONBLOCK\n");
-	exit(0);
+	return 0;
 #endif
 #ifdef O_NDELAY
 	printf("O_NDELAY\n");
-	exit(0);
+	return 0;
 #endif
 ?X: Stevens "Advanced Programming in the UNIX Environment" page 364 mentions
 ?X: the FNDELAY symbol, used in 4.33BSD (source: Paul Marquess).
 #ifdef FNDELAY
 	printf("FNDELAY\n");
-	exit(0);
 #endif
-	exit(0);
+	return 0;
 }
 EOCP
 	if $cc $ccflags $ldflags -o try try.c >/dev/null 2>&1; then
@@ -132,6 +138,7 @@ case "$eagain" in
 #include <errno.h>
 #include <sys/types.h>
 #include <signal.h>
+#include <stdlib.h>
 #define MY_O_NONBLOCK $o_nonblock
 extern int errno;
 $signal_t blech(x) int x; { exit(3); }
@@ -184,7 +191,7 @@ int main()
 	close(pu[1]);			/* We read from pu[0] */
 	read(pu[0], buf, 1);	/* Wait for parent to signal us we may continue */
 	close(pd[1]);			/* Pipe pd is now fully closed! */
-	exit(0);				/* Bye bye, thank you for playing! */
+	return 0;			/* Bye bye, thank you for playing! */
 }
 EOCP
 	if $cc $ccflags $ldflags -o try try.c >/dev/null 2>&1; then
diff --git a/mcon/U/orderlib.U b/mcon/U/orderlib.U
index 0c77e54..1c0feb7 100644
--- a/mcon/U/orderlib.U
+++ b/mcon/U/orderlib.U
@@ -51,7 +51,7 @@ echo "Checking how to generate random libraries on your machine..." >&4
 echo 'int bar1() { return bar2(); }' > bar1.c
 echo 'int bar2() { return 2; }' > bar2.c
 $cat > foo.c <<'EOP'
-int main() { printf("%d\n", bar1()); exit(0); }
+int main() { printf("%d\n", bar1()); return 0; }
 EOP
 $cc $ccflags -c bar1.c >/dev/null 2>&1
 $cc $ccflags -c bar2.c >/dev/null 2>&1
diff --git a/mcon/U/prototype.U b/mcon/U/prototype.U
index ec65247..f254e2c 100644
--- a/mcon/U/prototype.U
+++ b/mcon/U/prototype.U
@@ -102,10 +102,9 @@
 echo " "
 echo "Checking out function prototypes..." >&4
 $cat >prototype.c <<'EOCP'
-int main(int argc, char *argv[]) {
-	exit(0);}
+int main(int argc, char *argv[]) { (void) argc; (void) argv; return 0; }
 EOCP
-if $cc $ccflags -c prototype.c >prototype.out 2>&1 ; then
+if $cc $ccflags -c prototype.c; then
 	echo "Your C compiler appears to support function prototypes."
 	val="$define"
 else