[PATCH, obvious] Fix PR c/115587, uninitialized variable in c_parser_omp_loop_nest

[Sandra Loosemore]

This function had a reference to an uninitialized variable on the
error path.  The problem was diagnosed by clang but not gcc.  It seems
the cleanest solution is to initialize all the loop-clause variables
at the point of declaration rather than at different places in the
code.

The C++ front end didn't have this problem, but I've made similar
changes there to keep the code in sync.

gcc/c/ChangeLog:

        PR c/115587
        * c-parser.cc (c_parser_omp_loop_nest): Move initializations to
        point of declaration.

gcc/cp/ChangeLog:

        PR c/115587
        * parser.cc (cp_parser_omp_loop_nest): Move initializations to
        point of declaration.
---
 gcc/c/c-parser.cc | 4 +---
 gcc/cp/parser.cc  | 8 ++------
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/gcc/c/c-parser.cc b/gcc/c/c-parser.cc
index e83e9c683f7..33643ec910a 100644
--- a/gcc/c/c-parser.cc
+++ b/gcc/c/c-parser.cc
@@ -22430,7 +22430,7 @@ static tree c_parser_omp_unroll (location_t, c_parser 
*, bool *);
 static tree
 c_parser_omp_loop_nest (c_parser *parser, bool *if_p)
 {
-  tree decl, cond, incr, init;
+  tree decl = NULL_TREE, cond = NULL_TREE, incr = NULL_TREE, init = NULL_TREE;
   tree body = NULL_TREE;
   matching_parens parens;
   bool moreloops;
@@ -22619,7 +22619,6 @@ c_parser_omp_loop_nest (c_parser *parser, bool *if_p)
     }
 
   /* Parse the loop condition.  */
-  cond = NULL_TREE;
   if (c_parser_next_token_is_not (parser, CPP_SEMICOLON))
     {
       location_t cond_loc = c_parser_peek_token (parser)->location;
@@ -22652,7 +22651,6 @@ c_parser_omp_loop_nest (c_parser *parser, bool *if_p)
   c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
 
   /* Parse the increment expression.  */
-  incr = NULL_TREE;
   if (c_parser_next_token_is_not (parser, CPP_CLOSE_PAREN))
     {
       location_t incr_loc = c_parser_peek_token (parser)->location;
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index e7409b856f1..e5f16fe963d 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -45153,8 +45153,8 @@ static tree cp_parser_omp_tile (cp_parser *, cp_token 
*, bool *);
 static tree
 cp_parser_omp_loop_nest (cp_parser *parser, bool *if_p)
 {
-  tree decl, cond, incr, init;
-  tree orig_init, real_decl, orig_decl;
+  tree decl = NULL_TREE, cond = NULL_TREE, incr = NULL_TREE, init = NULL_TREE;
+  tree orig_init = NULL_TREE, real_decl = NULL_TREE, orig_decl = NULL_TREE;
   tree init_block, body_block;
   tree init_placeholder, body_placeholder;
   tree init_scope;
@@ -45324,8 +45324,6 @@ cp_parser_omp_loop_nest (cp_parser *parser, bool *if_p)
   if (!parens.require_open (parser))
     return NULL;
 
-  init = orig_init = decl = real_decl = orig_decl = NULL_TREE;
-
   init_placeholder = build_stmt (input_location, EXPR_STMT,
                                 integer_zero_node);
   vec_safe_push (omp_for_parse_state->init_placeholderv, init_placeholder);
@@ -45501,12 +45499,10 @@ cp_parser_omp_loop_nest (cp_parser *parser, bool 
*if_p)
        }
     }
 
-  cond = NULL;
   if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON))
     cond = cp_parser_omp_for_cond (parser, decl, omp_for_parse_state->code);
   cp_parser_require (parser, CPP_SEMICOLON, RT_SEMICOLON);
 
-  incr = NULL;
   if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN))
     {
       /* If decl is an iterator, preserve the operator on decl
-- 
2.25.1