Merge branch 'gawk-4.1-stable'

7 files changed, 63 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 3931f564..020dd5f3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2014-09-01         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* builtin.c (do_substr): Return "" instead of null string in case
+	result is passed to length() with --lint. Based on discussions in
+	comp.lang.awk.
+
+	Unrelated:
+
+	* interpret.h (r_interpret): For indirect function call, separate
+	error message if lookup returned NULL. Otherwise got a core dump.
+	Thanks to "Kenny McKormack" for the report in comp.lang.awk.
+
 2014-08-27         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* configure.ac: Add test for strcasecmp.
diff --git a/builtin.c b/builtin.c
index 934664b0..1c794be7 100644
--- a/builtin.c
+++ b/builtin.c
@@ -1759,7 +1759,14 @@ do_substr(int nargs)
 			else if (do_lint == DO_LINT_INVALID && ! (d_length >= 0))
 				lintwarn(_("substr: length %g is not >= 0"), d_length);
 			DEREF(t1);
-			return dupnode(Nnull_string);
+			/*
+			 * Return explicit null string instead of doing
+			 * dupnode(Nnull_string) so that if the result
+			 * is checked with the combination of length()
+			 * and lint, no error is reported about using
+			 * an uninitialized value. Same thing later, too.
+			 */
+			return make_string("", 0);
 		}
 		if (do_lint) {
 			if (double_to_int(d_length) != d_length)
@@ -1813,7 +1820,7 @@ do_substr(int nargs)
 		if (do_lint && (do_lint == DO_LINT_ALL || ((indx | length) != 0)))
 			lintwarn(_("substr: source string is zero length"));
 		DEREF(t1);
-		return dupnode(Nnull_string);
+		return make_string("", 0);
 	}
 
 	/* get total len of input string, for following checks */
@@ -1830,7 +1837,7 @@ do_substr(int nargs)
 			lintwarn(_("substr: start index %g is past end of string"),
 				d_index);
 		DEREF(t1);
-		return dupnode(Nnull_string);
+		return make_string("", 0);
 	}
 	if (length > src_len - indx) {
 		if (do_lint)
diff --git a/doc/ChangeLog b/doc/ChangeLog
index 4eaa8138..69069fd2 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -1,3 +1,9 @@
+2014-09-01         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* gaktexi.in: Add index entry for @ - @load, @include,
+	and indirect function calls. Thanks to "Kenny McKormack" in
+	comp.lang.awk.
+
 2014-08-29         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* gawktexi.in: Continuing on reviewer comments, and other
diff --git a/doc/gawk.info b/doc/gawk.info
index afa825cc..f4b2b913 100644
--- a/doc/gawk.info
+++ b/doc/gawk.info
@@ -31205,6 +31205,10 @@ Index
 * ? (question mark), regexp operator <1>: GNU Regexp Operators.
                                                               (line  59)
 * ? (question mark), regexp operator:    Regexp Operators.    (line 111)
+* @-notation for indirect function calls: Indirect Calls.     (line  47)
+* @include directive:                    Include Files.       (line   8)
+* @load directive:                       Loading Shared Libraries.
+                                                              (line   8)
 * [] (square brackets), regexp operator: Regexp Operators.    (line  56)
 * \ (backslash):                         Comments.            (line  50)
 * \ (backslash), \" escape sequence:     Escape Sequences.    (line  84)
@@ -32274,6 +32278,8 @@ Index
 * extensions, common, single character fields: Single Character Fields.
                                                               (line   6)
 * extensions, in gawk, not in POSIX awk: POSIX/GNU.           (line   6)
+* extensions, loading, @load directive:  Loading Shared Libraries.
+                                                              (line   8)
 * extensions, mawk:                      Common Extensions.   (line   6)
 * extensions, where to find:             gawkextlib.          (line   6)
 * extract.awk program:                   Extract Program.     (line  79)
@@ -32324,6 +32330,7 @@ Index
 * FIELDWIDTHS variable <1>:              User-modified.       (line  37)
 * FIELDWIDTHS variable:                  Constant Size.       (line  23)
 * file descriptors:                      Special FD.          (line   6)
+* file inclusion, @include directive:    Include Files.       (line   8)
 * file names, distinguishing:            Auto-set.            (line  56)
 * file names, in compatibility mode:     Special Caveats.     (line   9)
 * file names, standard streams in gawk:  Special FD.          (line  46)
@@ -32450,6 +32457,7 @@ Index
 * FUNCTAB array:                         Auto-set.            (line 123)
 * function calls:                        Function Calls.      (line   6)
 * function calls, indirect:              Indirect Calls.      (line   6)
+* function calls, indirect, @-notation for: Indirect Calls.   (line  47)
 * function definition example:           Function Example.    (line   6)
 * function pointers:                     Indirect Calls.      (line   6)
 * functions, arrays as parameters to:    Pass By Value/Reference.
@@ -32730,10 +32738,12 @@ Index
 * in operator, testing if array element exists: Reference to Elements.
                                                               (line  38)
 * in operator, use in loops:             Scanning an Array.   (line  17)
+* including files, @include directive:   Include Files.       (line   8)
 * increment operators:                   Increment Ops.       (line   6)
 * index:                                 String Functions.    (line 155)
 * indexing arrays:                       Array Intro.         (line  50)
 * indirect function calls:               Indirect Calls.      (line   6)
+* indirect function calls, @-notation:   Indirect Calls.      (line  47)
 * infinite precision:                    Arbitrary Precision Arithmetic.
                                                               (line   6)
 * info debugger command:                 Debugger Info.       (line  13)
@@ -32906,6 +32916,8 @@ Index
 * list debugger command:                 Miscellaneous Debugger Commands.
                                                               (line  72)
 * list function definitions, in debugger: Debugger Info.      (line  30)
+* loading extensions, @load directive:   Loading Shared Libraries.
+                                                              (line   8)
 * loading, extensions:                   Options.             (line 173)
 * local variables, in a function:        Variable Scope.      (line   6)
 * locale categories:                     Explaining gettext.  (line  81)
diff --git a/doc/gawk.texi b/doc/gawk.texi
index 74dd35f8..6d37c556 100644
--- a/doc/gawk.texi
+++ b/doc/gawk.texi
@@ -4435,6 +4435,9 @@ to @code{EXIT_FAILURE}.
 
 This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
+@cindex @code{@@include} directive
+@cindex file inclusion, @code{@@include} directive
+@cindex including files, @code{@@include} directive
 The @code{@@include} keyword can be used to read external @command{awk} source
 files.  This gives you the ability to split large @command{awk} source files
 into smaller, more manageable pieces, and also lets you reuse common @command{awk}
@@ -4554,6 +4557,9 @@ and this also applies to files named with @code{@@include}.
 
 This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
+@cindex @code{@@load} directive
+@cindex loading extensions, @code{@@load} directive
+@cindex extensions, loading, @code{@@load} directive
 The @code{@@load} keyword can be used to read external @command{awk} extensions
 (stored as system shared libraries).
 This allows you to link in compiled code that may offer superior
@@ -19851,6 +19857,9 @@ This style of programming works, but can be awkward.  With @dfn{indirect}
 function calls, you tell @command{gawk} to use the @emph{value} of a
 variable as the name of the function to call.
 
+@cindex @code{@@}-notation for indirect function calls
+@cindex indirect function calls, @code{@@}-notation
+@cindex function calls, indirect, @code{@@}-notation for
 The syntax is similar to that of a regular function call: an identifier
 immediately followed by a left parenthesis, any arguments, and then
 a closing right parenthesis, with the addition of a leading @samp{@@}
diff --git a/doc/gawktexi.in b/doc/gawktexi.in
index 8091e16c..589c50b2 100644
--- a/doc/gawktexi.in
+++ b/doc/gawktexi.in
@@ -4346,6 +4346,9 @@ to @code{EXIT_FAILURE}.
 
 This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
+@cindex @code{@@include} directive
+@cindex file inclusion, @code{@@include} directive
+@cindex including files, @code{@@include} directive
 The @code{@@include} keyword can be used to read external @command{awk} source
 files.  This gives you the ability to split large @command{awk} source files
 into smaller, more manageable pieces, and also lets you reuse common @command{awk}
@@ -4465,6 +4468,9 @@ and this also applies to files named with @code{@@include}.
 
 This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
+@cindex @code{@@load} directive
+@cindex loading extensions, @code{@@load} directive
+@cindex extensions, loading, @code{@@load} directive
 The @code{@@load} keyword can be used to read external @command{awk} extensions
 (stored as system shared libraries).
 This allows you to link in compiled code that may offer superior
@@ -18978,6 +18984,9 @@ This style of programming works, but can be awkward.  With @dfn{indirect}
 function calls, you tell @command{gawk} to use the @emph{value} of a
 variable as the name of the function to call.
 
+@cindex @code{@@}-notation for indirect function calls
+@cindex indirect function calls, @code{@@}-notation
+@cindex function calls, indirect, @code{@@}-notation for
 The syntax is similar to that of a regular function call: an identifier
 immediately followed by a left parenthesis, any arguments, and then
 a closing right parenthesis, with the addition of a leading @samp{@@}
diff --git a/interpret.h b/interpret.h
index c26a9d46..be017355 100644
--- a/interpret.h
+++ b/interpret.h
@@ -1038,7 +1038,11 @@ match_re:
 				f = lookup(t1->stptr);
 			}
 
-			if (f == NULL || f->type != Node_func) {
+			if (f == NULL) {
+				/* FIXME: See if function is a built-in and try to call it */
+				fatal(_("`%s' is not a user-defined function, so it cannot be called indirectly"),
+						t1->stptr);
+			} else if(f->type != Node_func) {
 				if (f->type == Node_ext_func || f->type == Node_old_ext_func)
 					fatal(_("cannot (yet) call extension functions indirectly"));
 				else