This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[patch] tree-ssa.c: Fix PR tree-optimization/17506.
- From: Kazu Hirata <kazu at codesourcery dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: nathan at codesourcery dot com, joern dot rennecke at st dot com, reichelt at igpm dot rwth-aachen dot de
- Date: Sun, 27 Aug 2006 22:20:51 -0700
- Subject: [patch] tree-ssa.c: Fix PR tree-optimization/17506.
Hi,
Attached is a patch to fix PR tree-optimization/17506. (I merely
tested the patch attached to the PR.)
Given the testcase, gcc without this patch issues
pr17506.c: In function âbarâ:
pr17506.c:11: warning: âjâ is used uninitialized in this function
With this patch, gcc issues
pr17506.c: In function âbarâ:
pr17506.c:11: warning: âjâ is used uninitialized in this function
pr17506.c:21: note: âjâ was declared here
Notice that this patch adds a note. I personally feel that the
warning at line 11 is still confusing, but I am hoping that the note
will alleviate the confusion.
The patch issues the note whenever the unused variable is declared
outside the current function being compiled.
Tested on x86_64-pc-linux-gnu. OK to apply?
Kazu Hirata
2006-08-28 Nathan Sidwell <nathan@codesourcery.com>
J"orn Rennecke <joern.rennecke@st.com>
PR tree-optimization/17506
* tree-ssa.c (warn_uninit): If warning about a location outside of
the current function, note where the variable was declared.
2006-08-28 Volker Reichelt <reichelt@igpm.rwth-aachen.de>
Kazu Hirata <kazu@codesourcery.com>
PR tree-optimization/17506
* pr17506.c: New.
Index: tree-ssa.c
===================================================================
--- tree-ssa.c (revision 116501)
+++ tree-ssa.c (working copy)
@@ -1154,7 +1154,7 @@ warn_uninit (tree t, const char *gmsgid,
tree var = SSA_NAME_VAR (t);
tree def = SSA_NAME_DEF_STMT (t);
tree context = (tree) data;
- location_t * locus;
+ location_t *locus, *fun_locus;
/* Default uses (indicated by an empty definition statement),
are uninitialized. */
@@ -1178,6 +1178,12 @@ warn_uninit (tree t, const char *gmsgid,
? EXPR_LOCUS (context)
: &DECL_SOURCE_LOCATION (var));
warning (0, gmsgid, locus, var);
+ fun_locus = &DECL_SOURCE_LOCATION(cfun->decl);
+ if (locus->file != fun_locus->file
+ || locus->line < fun_locus->line
+ || locus->line > cfun->function_end_locus.line)
+ inform ("%J%qD was declared here", var, var);
+
TREE_NO_WARNING (var) = 1;
}
Index: testsuite/gcc.dg/pr17506.c
===================================================================
--- testsuite/gcc.dg/pr17506.c (revision 0)
+++ testsuite/gcc.dg/pr17506.c (revision 0)
@@ -0,0 +1,24 @@
+/* PR tree-optimization/17506
+ We issue an uninitialized variable warning at a wrong location at
+ line 11, which is very confusing. Make sure we print out a note to
+ make it less confusing. */
+/* { dg-do compile } */
+/* { dg-options "-O1 -Wuninitialized" } */
+
+inline int
+foo (int i)
+{
+ if (i) /* { dg-warning "used uninitialized in this function" } */
+ return 1;
+ return 0;
+}
+
+void baz (void);
+
+void
+bar (void)
+{
+ int j; /* { dg-error "note: 'j' was declared here" } */
+ for (; foo (j); ++j)
+ baz ();
+}