From 8a40fef3106214c7755971f3e27c715b3968ddf4 Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Thu, 19 May 2016 20:29:07 +0000 Subject: PR c/71171: Fix uninitialized source_range in c_parser_postfix_expression A common way for a c_expr to have an uninitialized src_range is in error-handling, where the "value" field is set to error_mark_node without touching the src_range, leading to complaints from valgrind. This patch introduces a new method c_expr::set_error which sets the value to error_mark_node whilst initializing the src_range to UNKNOWN_LOCATION. This fixes the valgrind issue seen in PR c/71171, along with various other related issues seen when running the testsuite using the checker patch I posted here: https://gcc.gnu.org/ml/gcc-patches/2015-12/msg00887.html (this checker still doesn't fully work yet, but it seems to be good for easily detecting these issues without needing Valgrind). gcc/c/ChangeLog: PR c/71171 * c-parser.c (c_parser_generic_selection): Use c_expr::set_error in error-handling. (c_parser_postfix_expression): Likewise. * c-tree.h (c_expr::set_error): New method. * c-typeck.c (parser_build_binary_op): In error-handling, ensure that result's range is initialized. From-SVN: r236488 --- gcc/c/c-tree.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'gcc/c/c-tree.h') diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h index 4a0236d..444e9a4 100644 --- a/gcc/c/c-tree.h +++ b/gcc/c/c-tree.h @@ -143,6 +143,15 @@ struct c_expr of this expression. */ location_t get_start () const { return src_range.m_start; } location_t get_finish () const { return src_range.m_finish; } + + /* Set the value to error_mark_node whilst ensuring that src_range + is initialized. */ + void set_error () + { + value = error_mark_node; + src_range.m_start = UNKNOWN_LOCATION; + src_range.m_finish = UNKNOWN_LOCATION; + } }; /* Type alias for struct c_expr. This allows to use the structure -- cgit v1.1