Expand preprocessor macros in C expressions.

* c-lang.h: #include "macroexp.h", for macro_lookup_ftype.
(scan_macro_expansion, scanning_macro_expansion,
finished_macro_expansion): New function declarations.
(expression_macro_lookup_func, expression_macro_lookup_baton): New
variable declarations.
* parser-defs.h (expression_context_pc): New declaration.
* parse.c (expression_context_pc): New variable.
(parse_exp_1): Set expression_context_pc, as well as
expression_context_block.
* c-exp.y (yylex): If we're not already reading the result of a
macro expansion, try to macro-expand the next token.  When we're
done scanning a macro expansion, switch back to the mainline text.
Commas and `if's in a macro's expansion don't terminate the input.
* c-lang.c: #include "macroscope.h" and "gdb_assert.h".
(macro_original_text, macro_expanded_text,
expression_macro_lookup_func, expression_macro_lookup_baton): New
variables.
(scan_macro_expansion, scanning_macro_expansion,
finished_macro_expansion, scan_macro_cleanup, null_macro_lookup,
c_preprocess_and_parse): New functions.
(c_language_defn, cplus_language_defn, asm_language_defn): Call
c_preprocess_and_parse, instead of c_parse.
* Makefile.in (c_lang_h): Note that this #includes macroexp.h.
(c-lang.o): Note dependency on macroscope.h and gdb_assert.h.

1 files changed, 8 insertions, 1 deletions

diff --git a/gdb/parse.c b/gdb/parse.c
index 9c1f3e1..bc81f22 100644
--- a/gdb/parse.c
+++ b/gdb/parse.c
@@ -71,6 +71,7 @@ struct expression *expout;
 int expout_size;
 int expout_ptr;
 struct block *expression_context_block;
+CORE_ADDR expression_context_pc;
 struct block *innermost_block;
 int arglist_len;
 union type_stack_elt *type_stack;
@@ -1140,7 +1141,13 @@ parse_exp_1 (char **stringptr, struct block *block, int comma)
   old_chain = make_cleanup (free_funcalls, 0 /*ignore*/);
   funcall_chain = 0;
 
-  expression_context_block = block ? block : get_selected_block (0);
+  if (block)
+    {
+      expression_context_block = block;
+      expression_context_pc = block->startaddr;
+    }
+  else
+    expression_context_block = get_selected_block (&expression_context_pc);
 
   namecopy = (char *) alloca (strlen (lexptr) + 1);
   expout_size = 10;