Hi!
The standard says http://eel.is/c++draft/cpp.cond#7.sentence-2 that
__has_include can't appear at arbitrary places in the source. As we have
not recognized __has_include* outside of preprocessing directives in the
past, accepting it there now would be a regression. The patch does still
allow it in #define if it is then used in preprocessing directives, I guess
that use isn't strictly valid either, but clang seems to accept it.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2020-02-04 Jakub Jelinek
* macro.c (builtin_has_include): Diagnose __has_include* use outside
of preprocessing directives.
* c-c++-common/cpp/has-include-1.c: New test.
* c-c++-common/cpp/has-include-next-1.c: New test.
* c-c++-common/gomp/has-include-1.c: New test.
--- libcpp/macro.c.jj 2020-02-03 14:25:52.511004543 +0100
+++ libcpp/macro.c 2020-02-03 14:29:13.505038048 +0100
@@ -359,6 +359,11 @@ builtin_has_include (cpp_reader *pfile,
{
int result = 0;
+ if (!pfile->state.in_directive)
+cpp_error (pfile, CPP_DL_ERROR,
+ "\"%s\" used outside of preprocessing directive",
+ NODE_NAME (op));
+
pfile->state.angled_headers = true;
const cpp_token *token = cpp_get_token_no_padding (pfile);
bool paren = token->type == CPP_OPEN_PAREN;
--- gcc/testsuite/c-c++-common/cpp/has-include-1.c.jj 2020-02-03
15:03:17.970839759 +0100
+++ gcc/testsuite/c-c++-common/cpp/has-include-1.c 2020-02-03
15:14:11.598180968 +0100
@@ -0,0 +1,104 @@
+/* { dg-do preprocess } */
+
+#if __has_include ("stdlib.h")
+#else
+#error error 1
+#endif
+#if __has_include ()
+#else
+#error error 2
+#endif
+#if !__has_include ("stdlib.h")
+#error error 3
+#elif !__has_include ()
+#error error 4
+#endif
+#if __has_include ("stdlib.h") && __has_include ()
+#else
+#error error 5
+#endif
+#if !defined(__has_include)
+#error error 6
+#endif
+#ifndef __has_include
+#error error 7
+#endif
+#ifdef __has_include
+#else
+#error error 8
+#endif
+#define m1 __has_include("stdlib.h")
+#define m2 ("stdlib.h")
+#define m3 ("has-include-1-nonexistent.h")
+#define m4 has-include-1-nonexistent-2.h>)
+#define m5
+#if !m1
+#error error 9
+#endif
+#if !__has_include m2
+#error error 10
+#endif
+#if __has_include m3
+#error error 11
+#endif
+#if __has_include () /* { dg-error "used outside of
preprocessing directive" } */
+m1 /* { dg-error "used outside of
preprocessing directive" } */
+#if 1
+m1 /* { dg-error "used outside of
preprocessing directive" } */
+#endif
+#if 0
+#elif 1
+m1 /* { dg-error "used outside of
preprocessing directive" } */
+#endif
+#if 0
+m1
+#endif
+#if 0
+#elif 0
+m1
+#endif
+#if __has_include "stdlib.h") /* { dg-error "missing" } */
+#endif
+#if __has_include (stdlib.h) /* { dg-error "operator|missing" } */
+#endif
+#if __has_include () /* { dg-error "operator|missing" } */
+#endif
+#if __has_include )/* { dg-error "operator|missing" } */
+#endif
+#if __has_include ("stdlib.h)
+#endif
+/* { dg-error "operator|missing\[^\n\r]*after" "" { target *-*-* } .-2 } */
+/* { dg-warning "missing terminating" "" { target *-*-* } .-3 } */
+#if __has_include (stdlib.h>) /* { dg-error "operator|missing" } */
+#endif
+#if __has_include ("stdlib.h" /* { dg-error "missing" } */
+#endif
+#if __has_include (/* { dg-error "operator|missing" } */
+#endif
+#if __has_include /* { dg-error "operator|missing" } */
+#endif
+#if __has_include"stdlib.h"/* { dg-error "missing" } */
+#endif
+#if __has_include'h' /* { dg-error "operator|missing" } */
+#endif
+#if __has_include('h' /* { dg-error "operator|missing" } */
+#endif
+#if __has_include('h') /* { dg-error "operator" } */
+#endif
+#define H(h) __has_include(h)
+#if H()
+#else
+#error error 14
+#endif
+void
+foo ()
+{
+#pragma omp parallel if (__has_include (""))
+ ;
+}
--- gcc/testsuite/c-c++-common/cpp/has-include-next-1.c.jj 2020-02-03
15:19:05.068844085 +0100
+++ gcc/testsuite/c-c++-common/cpp/has-include-next-1.c 2020-02-03
15:19:39.993327980 +0100
@@ -0,0 +1,104 @@
+/* { dg-do preprocess } */
+
+#if __has_include_next ("stdlib.h")
+#else
+#error error 1
+#endif
+#if __has_include_next ()
+#else
+#error error 2
+#endif
+#if !__has_include_next ("stdlib.h")
+#error error 3
+#elif !__has_include_next ()
+#error error 4
+#endif
+#if __has_include_next ("stdlib.h") && __has_include_next ()
+#else
+#error error 5
+#endif
+#if !defined(__has_include_next)
+#error error 6
+#endif
+#ifndef __has_include_next
+#error error 7
+#endif
+#ifdef __has_include_next
+#else
+#error error 8
+#endif
+#define m1 __has_include_next("stdlib.h")
+#define m2 ("stdlib.h")
+#define m3 ("has-include-1-nonexistent.h")
+#define m4
