bpo-46237: Fix the line number of tokenizer errors inside f-strings (GH-30463)

(cherry picked from commit 6fa8b2ceee38187b0ae96aee12fe4f0a5c8a2ce7)

Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>
diff --git a/Parser/pegen.c b/Parser/pegen.c
index 0504906..e507415 100644
--- a/Parser/pegen.c
+++ b/Parser/pegen.c
@@ -701,10 +701,10 @@ initialize_token(Parser *p, Token *token, const char *start, const char *end, in
     int col_offset = (start != NULL && start >= line_start) ? (int)(start - line_start) : -1;
     int end_col_offset = (end != NULL && end >= p->tok->line_start) ? (int)(end - p->tok->line_start) : -1;
 
-    token->lineno = p->starting_lineno + lineno;
-    token->col_offset = p->tok->lineno == 1 ? p->starting_col_offset + col_offset : col_offset;
-    token->end_lineno = p->starting_lineno + end_lineno;
-    token->end_col_offset = p->tok->lineno == 1 ? p->starting_col_offset + end_col_offset : end_col_offset;
+    token->lineno = lineno;
+    token->col_offset = p->tok->lineno == p->starting_lineno ? p->starting_col_offset + col_offset : col_offset;
+    token->end_lineno = end_lineno;
+    token->end_col_offset = p->tok->lineno == p->starting_lineno ? p->starting_col_offset + end_col_offset : end_col_offset;
 
     p->fill += 1;
 
diff --git a/Parser/string_parser.c b/Parser/string_parser.c
index dcd298c..c83e63f 100644
--- a/Parser/string_parser.c
+++ b/Parser/string_parser.c
@@ -392,11 +392,14 @@ fstring_compile_expr(Parser *p, const char *expr_start, const char *expr_end,
         return NULL;
     }
     Py_INCREF(p->tok->filename);
+
     tok->filename = p->tok->filename;
+    tok->lineno = t->lineno + lines - 1;
 
     Parser *p2 = _PyPegen_Parser_New(tok, Py_fstring_input, p->flags, p->feature_version,
                                      NULL, p->arena);
-    p2->starting_lineno = t->lineno + lines - 1;
+
+    p2->starting_lineno = t->lineno + lines;
     p2->starting_col_offset = t->col_offset + cols;
 
     expr = _PyPegen_run_parser(p2);