From: Martin Sebor <msebor@redhat.com>
Date: Fri, 30 Aug 2019 17:49:17 +0000 (+0000)
Subject: PR middle-end/91599 - GCC does not say where warning is happening
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=648af1684557e24e54a67b95b57fae2646cc2b56;p=gcc.git

PR middle-end/91599 - GCC does not say where warning is happening

gcc/ChangeLog:

	PR middle-end/91599
	* tree-ssa-strlen.c (handle_store): Use a fallback location if
	the statement doesn't have one.
	* gimple-pretty-print.c (percent_G_format): Same.

gcc/testsuite/ChangeLog:

	PR middle-end/91599
	* gcc.dg/Wstringop-overflow-16.c: New test.

From-SVN: r275211
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 45dd3a28012..1a8026c63f2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
 2019-08-30  Martin Sebor  <msebor@redhat.com>
 
+	PR middle-end/91599
+	* tree-ssa-strlen.c (handle_store): Use a fallback location if
+	the statement doesn't have one.
+	* gimple-pretty-print.c (percent_G_format): Same.
+
 	PR middle-end/91584
 	* tree-vrp.c (vrp_prop::check_mem_ref): Normalize type domain bounds
 	before using them to validate MEM_REF offset.
diff --git a/gcc/gimple-pretty-print.c b/gcc/gimple-pretty-print.c
index ce339eeddac..2d5ece06805 100644
--- a/gcc/gimple-pretty-print.c
+++ b/gcc/gimple-pretty-print.c
@@ -3034,8 +3034,12 @@ percent_G_format (text_info *text)
 {
   gimple *stmt = va_arg (*text->args_ptr, gimple*);
 
+  /* Fall back on the rich location if the statement doesn't have one.  */
+  location_t loc = gimple_location (stmt);
+  if (loc == UNKNOWN_LOCATION)
+    loc = text->m_richloc->get_loc ();
   tree block = gimple_block (stmt);
-  percent_K_format (text, gimple_location (stmt), block);
+  percent_K_format (text, loc, block);
 }
 
 #if __GNUC__ >= 10
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 420ddd49b1f..83d17a38f6c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2019-08-30  Martin Sebor  <msebor@redhat.com>
 
+	PR middle-end/91599
+	* gcc.dg/Wstringop-overflow-16.c: New test.
+
 	PR middle-end/91584
 	* gfortran.dg/char_array_constructor_4.f90: New test.
 
diff --git a/gcc/testsuite/gcc.dg/Wstringop-overflow-16.c b/gcc/testsuite/gcc.dg/Wstringop-overflow-16.c
new file mode 100644
index 00000000000..74548a4f0fa
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Wstringop-overflow-16.c
@@ -0,0 +1,21 @@
+/* PR middle-end/91599 - GCC does not say where warning is happening
+   { dg-do compile }
+   { dg-options "-O2 -Wall" } */
+
+struct charseq {
+  unsigned char bytes[0];         // { dg-message "object declared here" }
+};
+
+struct locale_ctype_t {
+  struct charseq *mboutdigits[10];
+};
+
+void ctype_finish (struct locale_ctype_t *ctype)
+{
+  long unsigned int cnt;
+  for (cnt = 0; cnt < 20; ++cnt) {
+    static struct charseq replace[2];
+    replace[0].bytes[1] = '\0';   // { dg-warning "\\\[-Wstringop-overflow" }
+    ctype->mboutdigits[cnt] = &replace[0];
+  }
+}
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c
index 7bb5f52c1e5..b9793207a71 100644
--- a/gcc/tree-ssa-strlen.c
+++ b/gcc/tree-ssa-strlen.c
@@ -4036,7 +4036,12 @@ handle_store (gimple_stmt_iterator *gsi)
 	  if (tree dstsize = compute_objsize (lhs, 1, &decl))
 	    if (compare_tree_int (dstsize, lenrange[2]) < 0)
 	      {
+		/* Fall back on the LHS location if the statement
+		   doesn't have one.  */
 		location_t loc = gimple_nonartificial_location (stmt);
+		if (loc == UNKNOWN_LOCATION)
+		  loc = tree_nonartificial_location (lhs);
+		loc = expansion_point_location_if_in_system_header (loc);
 		if (warning_n (loc, OPT_Wstringop_overflow_,
 			       lenrange[2],
 			       "%Gwriting %u byte into a region of size %E",