Hello,
Is it OK to push the cleaning of TREE_NO_WARNING to fix the constant
expressions errors discrepancies, as discussed in bugzilla #52283, now
that the trunk is open ?
Many thanks,
2012-03-29 Manuel López-Ibáñez <m...@gcc.gnu.org>
PR c/52283/37985
* stmt.c (warn_if_unused_value): Skip NOP_EXPR.
* convert.c (convert_to_integer): Don't set TREE_NO_WARNING.
2010-03-29 Christian Bruel <christian.br...@st.com>
PR c/52283
* gcc.dg/case-const-1.c: Test constant expression.
* gcc.dg/case-const-2.c: Likewise.
* gcc.dg/case-const-3.c: Likewise.
2012-03-29 Manuel López-Ibáñez <m...@gcc.gnu.org>
* gcc/testsuite/gcc.dg/pr37985.c: New test.
Index: gcc/testsuite/gcc.dg/pr37985.c
===================================================================
--- gcc/testsuite/gcc.dg/pr37985.c (revision 0)
+++ gcc/testsuite/gcc.dg/pr37985.c (revision 0)
@@ -0,0 +1,8 @@
+/* PR c/37985 */
+/* { dg-do compile } */
+/* { dg-options " -Wall -Wextra " } */
+unsigned char foo(unsigned char a)
+{
+ a >> 2; /* { dg-warning "no effect" } */
+ return a;
+}
Index: gcc/testsuite/gcc.dg/case-const-1.c
===================================================================
--- gcc/testsuite/gcc.dg/case-const-1.c (revision 186082)
+++ gcc/testsuite/gcc.dg/case-const-1.c (working copy)
@@ -1,9 +1,11 @@
/* Test for case labels not integer constant expressions but folding
- to integer constants (used in Linux kernel, PR 39613). */
+ to integer constants (used in Linux kernel, PR 39613, 52283). */
/* { dg-do compile } */
/* { dg-options "" } */
extern int i;
+extern unsigned int u;
+
void
f (int c)
{
@@ -13,3 +15,13 @@
;
}
}
+
+void
+b (int c)
+{
+ switch (c)
+ {
+ case (int) (2 | ((4 < 8) ? 8 : u)):
+ ;
+ }
+}
Index: gcc/testsuite/gcc.dg/case-const-2.c
===================================================================
--- gcc/testsuite/gcc.dg/case-const-2.c (revision 186082)
+++ gcc/testsuite/gcc.dg/case-const-2.c (working copy)
@@ -1,9 +1,11 @@
/* Test for case labels not integer constant expressions but folding
- to integer constants (used in Linux kernel, PR 39613). */
+ to integer constants (used in Linux kernel, PR 39613, 52283). */
/* { dg-do compile } */
/* { dg-options "-pedantic" } */
extern int i;
+extern unsigned int u;
+
void
f (int c)
{
@@ -13,3 +15,14 @@
;
}
}
+
+void
+b (int c)
+{
+ switch (c)
+ {
+ case (int) (2 | ((4 < 8) ? 8 : u)): /* { dg-warning "case label is not an integer constant expression" } */
+ ;
+ }
+}
+
Index: gcc/testsuite/gcc.dg/case-const-3.c
===================================================================
--- gcc/testsuite/gcc.dg/case-const-3.c (revision 186082)
+++ gcc/testsuite/gcc.dg/case-const-3.c (working copy)
@@ -1,9 +1,11 @@
/* Test for case labels not integer constant expressions but folding
- to integer constants (used in Linux kernel, PR 39613). */
+ to integer constants (used in Linux kernel, PR 39613, 52283, ). */
/* { dg-do compile } */
/* { dg-options "-pedantic-errors" } */
extern int i;
+extern unsigned int u;
+
void
f (int c)
{
@@ -13,3 +15,16 @@
;
}
}
+
+void
+b (int c)
+{
+ switch (c)
+ {
+ case (int) (2 | ((4 < 8) ? 8 : u)): /* { dg-error "case label is not an integer constant expression" } */
+ ;
+ }
+}
+
+
+
Index: gcc/stmt.c
===================================================================
--- gcc/stmt.c (revision 186082)
+++ gcc/stmt.c (working copy)
@@ -1515,6 +1515,7 @@
case SAVE_EXPR:
case NON_LVALUE_EXPR:
+ case NOP_EXPR:
exp = TREE_OPERAND (exp, 0);
goto restart;
Index: gcc/convert.c
===================================================================
--- gcc/convert.c (revision 186082)
+++ gcc/convert.c (working copy)
@@ -542,7 +542,6 @@
else if (outprec >= inprec)
{
enum tree_code code;
- tree tem;
/* If the precision of the EXPR's type is K bits and the
destination mode has more bits, and the sign is changing,
@@ -560,13 +559,7 @@
else
code = NOP_EXPR;
- tem = fold_unary (code, type, expr);
- if (tem)
- return tem;
-
- tem = build1 (code, type, expr);
- TREE_NO_WARNING (tem) = 1;
- return tem;
+ return fold_build1 (code, type, expr);
}
/* If TYPE is an enumeral type or a type with a precision less
