On 6/25/24 04:01, Tamar Christina wrote:
Hi All,
It looks like I forgot to check in the C++ frontend if a condition exist for the
loop being adorned with novector. This causes a segfault because cond isn't
expected to be null.
This fixes it by issuing the same kind of diagnostics we issue for the other
pragmas.
Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
Ok for master? and backport to GCC-14?
Hmm, I'm not sure we want to error in this case; it's pointless, but
indeed we aren't going to vectorize a loop that always loops. I'd think
we should treat it the same as an explicit "true" condition. And
perhaps the same for unroll/ivdep.
Does the C front-end treat the null condition different from a constant
true condition?
Thanks,
Tamar
gcc/cp/ChangeLog:
PR c++/115623
* parser.cc (cp_parser_c_for): Add check for C++ cond.
gcc/testsuite/ChangeLog:
PR c++/115623
* g++.dg/vect/vect-novector-pragma_2.cc: New test.
---
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index
e7409b856f1127e303c6515a3bb2d61a10e7c378..24d7b0e4992fdff69951ac5955f304e473f53374
100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -14107,6 +14107,12 @@ cp_parser_c_for (cp_parser *parser, tree scope, tree
init, bool ivdep,
"%<GCC unroll%> pragma");
condition = error_mark_node;
}
+ else if (novector)
+ {
+ cp_parser_error (parser, "missing loop condition in loop with "
+ "%<GCC novector%> pragma");
+ condition = error_mark_node;
+ }
finish_for_cond (condition, stmt, ivdep, unroll, novector);
/* Look for the `;'. */
cp_parser_require (parser, CPP_SEMICOLON, RT_SEMICOLON);
diff --git a/gcc/testsuite/g++.dg/vect/vect-novector-pragma_2.cc
b/gcc/testsuite/g++.dg/vect/vect-novector-pragma_2.cc
new file mode 100644
index
0000000000000000000000000000000000000000..05dba4db1c6544bc53cd05482d1b2e767052cf43
--- /dev/null
+++ b/gcc/testsuite/g++.dg/vect/vect-novector-pragma_2.cc
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+
+void f (char *a, int i)
+{
+#pragma GCC novector
+ for (;;i++)
+ a[i] *= 2;
+}
+
+/* { dg-error "missing loop condition in loop with 'GCC novector' pragma before ';'
token" "" { target *-*-* } 6 } */
