gdb/

* macrocmd.c (info_macro_command): Print -Dname=value if LINE is zero.

gdb/doc/
	* gdb.texinfo (Macros): Note command-line for `info macro'.  Append
	a new part on command-line defined macros.

gdb/testsuite/
	* gdb.base/macscp.exp: New `options' parameter `-DFROM_COMMANDLINE'.
	(info_macro): Remova `decimal' declaration.  New variable `nonzero'.
	Replace all uses of `decimal' by `nonzero'.
	(info macro FROM_COMMANDLINE): New test.

gdb/ChangeLog

@@ -1,3 +1,7 @@
+2009-04-29  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* macrocmd.c (info_macro_command): Print -Dname=value if LINE is zero.
+
 2009-04-27  Tom Tromey  <tromey@redhat.com>
 
 	* c-exp.y (yylex): Handle '[' and ']' like '(' and ')'.

gdb/doc/ChangeLog

@@ -1,3 +1,8 @@
+2009-04-29  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* gdb.texinfo (Macros): Note command-line for `info macro'.  Append
+	a new part on command-line defined macros.
+
 2009-04-25  Eli Zaretskii  <eliz@gnu.org>
 
 	* gdb.texinfo (Machine Code) <disassemble-next-line>: Improve and

gdb/doc/gdb.texinfo

@@ -8382,7 +8382,7 @@ can be any string of tokens.
 @cindex definition, showing a macro's
 @item info macro @var{macro}
 Show the definition of the macro named @var{macro}, and describe the
-source location where that definition was established.
+source location or compiler command-line where that definition was established.
 
 @kindex macro define
 @cindex user-defined macros
@@ -8547,6 +8547,18 @@ $2 = 0
 (@value{GDBP})
 @end smallexample
 
+In addition to source files, macros can be defined on the compilation command
+line using the @option{-D@var{name}=@var{value}} syntax.  For macros defined in
+such a way, @value{GDBN} displays the location of their definition as line zero
+of the source file submitted to the compiler.
+
+@smallexample
+(@value{GDBP}) info macro __STDC__
+Defined at /home/jimb/gdb/macros/play/sample.c:0
+-D__STDC__=1
+(@value{GDBP})
+@end smallexample
+
 
 @node Tracepoints
 @chapter Tracepoints

gdb/macrocmd.c

@@ -158,7 +158,10 @@ info_macro_command (char *name, int from_tty)
 
       fprintf_filtered (gdb_stdout, "Defined at ");
       show_pp_source_pos (gdb_stdout, file, line);
-      fprintf_filtered (gdb_stdout, "#define %s", name);
+      if (line != 0)
+	fprintf_filtered (gdb_stdout, "#define %s", name);
+      else
+	fprintf_filtered (gdb_stdout, "-D%s", name);
       if (d->kind == macro_function_like)
         {
           int i;
@@ -172,7 +175,10 @@ info_macro_command (char *name, int from_tty)
             }
           fputs_filtered (")", gdb_stdout);
         }
-      fprintf_filtered (gdb_stdout, " %s\n", d->replacement);
+      if (line != 0)
+	fprintf_filtered (gdb_stdout, " %s\n", d->replacement);
+      else
+	fprintf_filtered (gdb_stdout, "=%s\n", d->replacement);
     }
   else
     {

gdb/testsuite/ChangeLog

@@ -1,3 +1,10 @@
+2009-04-29  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* gdb.base/macscp.exp: New `options' parameter `-DFROM_COMMANDLINE'.
+	(info_macro): Remova `decimal' declaration.  New variable `nonzero'.
+	Replace all uses of `decimal' by `nonzero'.
+	(info macro FROM_COMMANDLINE): New test.
+
 2009-04-27  Tom Tromey  <tromey@redhat.com>
 
 	* gdb.base/printcmds.exp (test_printf): Test comma operator in [].

gdb/testsuite/gdb.base/macscp.exp

@@ -26,7 +26,7 @@ set testfile "macscp"
 set objfile ${objdir}/${subdir}/${testfile}.o
 set binfile ${objdir}/${subdir}/${testfile}
 
-set options { debug }
+set options { debug additional_flags=-DFROM_COMMANDLINE=ARG}
 
 get_compiler_info ${binfile}
 if [test_compiler_info gcc*] {
@@ -67,19 +67,22 @@ gdb_load ${binfile}
 
 proc info_macro {macro} {
     global gdb_prompt
-    global decimal
 
     set filepat {macscp[0-9]+\.[ch]}
     set definition {}
     set location {}
 
+    # Line number zero is set for macros defined from the compiler command-line.
+    # Such macros are not being tested by this function.
+    set nonzero {[1-9][0-9]*}
+
     send_gdb "info macro ${macro}\n"
 
     set debug_me 0
 
     if {$debug_me} {exp_internal 1}
     gdb_expect {
-        -re "Defined at \[^\r\n\]*(${filepat}):${decimal}\[\r\n\]" {
+        -re "Defined at \[^\r\n\]*(${filepat}):${nonzero}\[\r\n\]" {
             # `location' and `definition' should be empty when we see
             # this message.
             if {[llength $location] == 0 && [llength $definition] == 0} {
@@ -101,7 +104,7 @@ proc info_macro {macro} {
                 set definition {}
             }
         }
-        -re "^\[\r\n\]*  included at \[^\r\n\]*(${filepat}):${decimal}\[\r\n\]" {
+        -re "^\[\r\n\]*  included at \[^\r\n\]*(${filepat}):${nonzero}\[\r\n\]" {
             # `location' should *not* be empty when we see this
             # message.  It should have recorded at least the initial
             # `Defined at ' message (for definitions) or ` at' message
@@ -114,7 +117,7 @@ proc info_macro {macro} {
                 set definition {}
             }
         }
-        -re "^\[\r\n\]*at \[^\r\n\]*(${filepat}):${decimal}\[\r\n\]" {
+        -re "^\[\r\n\]*at \[^\r\n\]*(${filepat}):${nonzero}\[\r\n\]" {
             # This appears after a `has no definition' message.
             # `location' should be empty when we see it.
             if {[string compare $definition undefined] == 0 \
@@ -205,6 +208,11 @@ list_and_check_macro macscp2_2 WHERE {macscp2.h macscp1.c {before macscp2_2}}
 list_and_check_macro macscp3_2 WHERE {macscp3.h macscp1.c {before macscp3_2}}
 
 
+# Assuming the current position inside program by `list' from above.
+gdb_test "info macro FROM_COMMANDLINE" \
+	 "Defined at \[^\r\n\]*:0\r\n-DFROM_COMMANDLINE=ARG"
+
+
 # Although GDB's macro table structures distinguish between multiple
 # #inclusions of the same file, GDB's other structures don't.  So the
 # `list' command here doesn't reliably select one #inclusion or the