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re PR c++/68979 (error: left operand of shift expression ‘(-1 << 4)’ is negative)

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PR c++/68979
	* constexpr.c (cxx_eval_check_shift_p): Use permerror rather than
	error_at and adjust the return value.

	* g++.dg/warn/permissive-1.C: New test.

From-SVN: r232280
This commit is contained in:
Marek Polacek 2016-01-12 16:48:29 +00:00 • committed by Marek Polacek
parent 324402a0c6
commit 5342156c7a
4 changed files with 33 additions and 13 deletions
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6
gcc/cp/ChangeLog
View file

@ -1,3 +1,9 @@
2016-01-12 Marek Polacek <polacek@redhat.com>
PR c++/68979
* constexpr.c (cxx_eval_check_shift_p): Use permerror rather than
error_at and adjust the return value.
2016-01-12 Jakub Jelinek <jakub@redhat.com>
PR objc++/68511

27
gcc/cp/constexpr.c
View file

@ -1512,17 +1512,17 @@ cxx_eval_check_shift_p (location_t loc, const constexpr_ctx *ctx,
if (tree_int_cst_sgn (rhs) == -1)
{
if (!ctx->quiet)
error_at (loc, "right operand of shift expression %q+E is negative",
build2_loc (loc, code, type, lhs, rhs));
return true;
permerror (loc, "right operand of shift expression %q+E is negative",
build2_loc (loc, code, type, lhs, rhs));
return (!flag_permissive || ctx->quiet);
}
if (compare_tree_int (rhs, uprec) >= 0)
{
if (!ctx->quiet)
error_at (loc, "right operand of shift expression %q+E is >= than "
"the precision of the left operand",
build2_loc (loc, code, type, lhs, rhs));
return true;
permerror (loc, "right operand of shift expression %q+E is >= than "
"the precision of the left operand",
build2_loc (loc, code, type, lhs, rhs));
return (!flag_permissive || ctx->quiet);
}
/* The value of E1 << E2 is E1 left-shifted E2 bit positions; [...]
@ -1536,9 +1536,10 @@ cxx_eval_check_shift_p (location_t loc, const constexpr_ctx *ctx,
if (tree_int_cst_sgn (lhs) == -1)
{
if (!ctx->quiet)
error_at (loc, "left operand of shift expression %q+E is negative",
build2_loc (loc, code, type, lhs, rhs));
return true;
permerror (loc,
"left operand of shift expression %q+E is negative",
build2_loc (loc, code, type, lhs, rhs));
return (!flag_permissive || ctx->quiet);
}
/* For signed x << y the following:
(unsigned) x >> ((prec (lhs) - 1) - y)
@ -1555,9 +1556,9 @@ cxx_eval_check_shift_p (location_t loc, const constexpr_ctx *ctx,
if (tree_int_cst_lt (integer_one_node, t))
{
if (!ctx->quiet)
error_at (loc, "shift expression %q+E overflows",
build2_loc (loc, code, type, lhs, rhs));
return true;
permerror (loc, "shift expression %q+E overflows",
build2_loc (loc, code, type, lhs, rhs));
return (!flag_permissive || ctx->quiet);
}
}
return false;

5
gcc/testsuite/ChangeLog
View file

@ -1,3 +1,8 @@
2016-01-12 Marek Polacek <polacek@redhat.com>
PR c++/68979
* g++.dg/warn/permissive-1.C: New test.
2016-01-12 Jakub Jelinek <jakub@redhat.com>
PR objc++/68511

8
gcc/testsuite/g++.dg/warn/permissive-1.C Normal file
View file

@ -0,0 +1,8 @@
// PR c++/68979
// { dg-do compile { target int32 } }
// { dg-options "-fpermissive -Wno-shift-overflow -Wno-shift-count-overflow -Wno-shift-count-negative" }
enum A { AA = -1 << 4 }; // { dg-warning "operand of shift expression" "" { target c++11 } }
enum B { BB = 1 << -4 }; // { dg-warning "operand of shift expression" }
enum C { CC = 1 << __SIZEOF_INT__ * 4 * __CHAR_BIT__ - 4 }; // { dg-warning "operand of shift expression" }
enum D { DD = 10 << __SIZEOF_INT__ * __CHAR_BIT__ - 2 }; // { dg-warning "shift expression" "" { target c++11 } }