2025-08-04 Jakub Jelinek <ja...@redhat.com>
PR preprocessor/120778
* macro.cc (paste_tokens): Use %< and %> instead of \" in
diagnostics around %.*s.
* g++.dg/DRs/dr2579.C: New test.
* c-c++-common/cpp/va-opt-6.c: Expect ' rather than \" around
tokens in incorrect pasting diagnostics.
* gcc.dg/c23-attr-syntax-6.c: Likewise.
* gcc.dg/cpp/paste12.c: Likewise.
* gcc.dg/cpp/paste12-2.c: Likewise.
* gcc.dg/cpp/paste14.c: Likewise.
* gcc.dg/cpp/paste14-2.c: Likewise.
--- libcpp/macro.cc.jj 2025-08-01 19:51:38.156038976 +0200
+++ libcpp/macro.cc 2025-08-04 16:49:57.489046833 +0200
@@ -1071,7 +1071,7 @@ paste_tokens (cpp_reader *pfile, locatio
/* Mandatory error for all apart from assembler. */
if (CPP_OPTION (pfile, lang) != CLK_ASM)
cpp_error_with_line (pfile, CPP_DL_ERROR, location, 0,
- "pasting \"%.*s\" and \"%.*s\" does not give "
+ "pasting %<%.*s%> and %<%.*s%> does not give "
"a valid preprocessing token",
(int) (lhsend - buf), buf,
(int) (end - rhsstart), rhsstart);
--- gcc/testsuite/g++.dg/DRs/dr2579.C.jj 2025-08-04 16:54:38.488305465
+0200
+++ gcc/testsuite/g++.dg/DRs/dr2579.C 2025-08-04 17:00:20.338756103 +0200
@@ -0,0 +1,9 @@
+// DR 2579 - Undefined behavior when token pasting does not create a
preprocessing token
+// { dg-do preprocess }
+// { dg-options "-pedantic-errors" }
+
+#define A(a, b) a ## b
+A(5,6)
+A(-,32) // { dg-error "pasting '-' and '32' does not give a
valid preprocessing token" }
+A("","") // { dg-error "pasting '\"\"' and '\"\"' does not give a valid
preprocessing token" }
+A(\,u0393)
--- gcc/testsuite/c-c++-common/cpp/va-opt-6.c.jj 2021-08-17
19:06:14.638793462 +0200
+++ gcc/testsuite/c-c++-common/cpp/va-opt-6.c 2025-08-04 16:51:20.749937055
+0200
@@ -3,15 +3,15 @@
/* { dg-options "-std=c++20" { target c++ } } */
#define a ""
-#define b(...) a ## #__VA_OPT__(1) /* { dg-error "pasting \"a\" and \"\"\"\"
does not give a valid preprocessing token" } */
-#define c(...) a ## #__VA_OPT__(1) /* { dg-error "pasting \"a\" and \"\"1\"\"
does not give a valid preprocessing token" } */
+#define b(...) a ## #__VA_OPT__(1) /* { dg-error "pasting 'a' and '\"\"' does
not give a valid preprocessing token" } */
+#define c(...) a ## #__VA_OPT__(1) /* { dg-error "pasting 'a' and '\"1\"' does
not give a valid preprocessing token" } */
#define d(...) #__VA_OPT__(1) ## !
#define e(...) #__VA_OPT__(1) ## !
#define f(...) #__VA_OPT__(. ## !)
#define g(...) #__VA_OPT__(. ## !)
b()
c(1)
-d( ) /* { dg-error "pasting \"\"\"\" and \"!\" does not give a valid
preprocessing token" } */
-e( 1 ) /* { dg-error "pasting \"\"1\"\" and \"!\" does not give a
valid preprocessing token" } */
+d( ) /* { dg-error "pasting '\"\"' and '!' does not give a valid
preprocessing token" } */
+e( 1 ) /* { dg-error "pasting '\"1\"' and '!' does not give a valid
preprocessing token" } */
f()
-g(0) /* { dg-error "pasting \".\" and \"!\" does not give a valid
preprocessing token" } */
+g(0) /* { dg-error "pasting '.' and '!' does not give a valid
preprocessing token" } */
--- gcc/testsuite/gcc.dg/c23-attr-syntax-6.c.jj 2024-02-22 22:34:18.838230561
+0100
+++ gcc/testsuite/gcc.dg/c23-attr-syntax-6.c 2025-08-04 16:52:14.086227176
+0200
@@ -45,7 +45,7 @@ typedef int [[__extension__ __extension_
typedef int [[__extension__ unknown_attribute]] b3; /* { dg-error
{'unknown_attribute' attribute ignored} } */
typedef int [[__extension__ gnu:vector_size(4)]] b4; /* { dg-error {expected
'\]' before ':'} } */
/* { dg-error {'gnu' attribute ignored} "" { target *-*-* } .-1 } */
-typedef int [[__extension__ gnu JOIN2(:,:) vector_size (4)]] b5; /* { dg-error {pasting
":" and ":" does not give a valid preprocessing token} } */
+typedef int [[__extension__ gnu JOIN2(:,:) vector_size (4)]] b5; /* { dg-error
{pasting ':' and ':' does not give a valid preprocessing token} } */
/* { dg-error {expected '\]' before ':'} "" { target *-*-* } .-1 } */
/* { dg-error {'gnu' attribute ignored} "" { target *-*-* } .-2 } */
typedef int [[__extension__ gnu : : vector_size (4)]] b6; /* { dg-error
{expected '\]' before ':'} } */
@@ -81,7 +81,7 @@ typedef int [[gnu :: vector_size (4)]] b
typedef int [[gnu FOO vector_size (4)]] b19; /* { dg-error {attributes before
C23} } */
typedef int [[gnu :: vector_size (sizeof (void (*)(...)))]] b20; /* {
dg-error {attributes before C23} } */
/* { dg-error {requires a named argument before} "" { target *-*-* } .-1 } */
-typedef int [[gnu JOIN2(:,:) vector_size (4)]] b21; /* { dg-error {pasting ":" and
":" does not give a valid preprocessing token} } */
+typedef int [[gnu JOIN2(:,:) vector_size (4)]] b21; /* { dg-error {pasting ':'
and ':' does not give a valid preprocessing token} } */
/* { dg-error {expected '\]' before ':'} "" { target *-*-* } .-1 } */
/* { dg-error {'gnu' attribute ignored} "" { target *-*-* } .-2 } */
/* { dg-error {attributes before C23} "" { target *-*-* } .-3 } */
--- gcc/testsuite/gcc.dg/cpp/paste12.c.jj 2020-01-14 20:02:47.258602719
+0100
+++ gcc/testsuite/gcc.dg/cpp/paste12.c 2025-08-04 16:53:34.867152142 +0200
@@ -8,4 +8,4 @@
#define inc2(a,b) <##a.b>
#define INC(X) inc2(X,h)
-#include INC(stdio) /* { dg-error "pasting \"<\" and \"stdio\" does not" } */
+#include INC(stdio) /* { dg-error "pasting '<' and 'stdio' does not" } */
--- gcc/testsuite/gcc.dg/cpp/paste12-2.c.jj 2020-01-14 20:02:47.258602719
+0100
+++ gcc/testsuite/gcc.dg/cpp/paste12-2.c 2025-08-04 16:53:12.255453058
+0200
@@ -6,6 +6,6 @@
/* Test correct diagnostics when pasting in #include.
Source: PR preprocessor/6780. */
-#define inc2(a,b) <##a.b> /* { dg-error "pasting \"<\" and \"stdio\" does not" } */
+#define inc2(a,b) <##a.b> /* { dg-error "pasting '<' and 'stdio' does not" }
*/
#define INC(X) inc2(X,h)
#include INC(stdio)
--- gcc/testsuite/gcc.dg/cpp/paste14.c.jj 2020-01-14 20:02:47.258602719
+0100
+++ gcc/testsuite/gcc.dg/cpp/paste14.c 2025-08-04 16:58:46.013011393 +0200
@@ -5,6 +5,6 @@
*/
#define foo - ## >>
-foo /* { dg-error "pasting \"-\" and \">>\"" } */
+foo /* { dg-error "pasting '-' and '>>'" } */
#define bar = ## ==
-bar /* { dg-error "pasting \"=\" and \"==\"" } */
+bar /* { dg-error "pasting '=' and '=='" } */
--- gcc/testsuite/gcc.dg/cpp/paste14-2.c.jj 2020-01-14 20:02:47.258602719
+0100
+++ gcc/testsuite/gcc.dg/cpp/paste14-2.c 2025-08-04 16:54:08.091709985
+0200
@@ -4,8 +4,8 @@
{ dg-do preprocess }
*/
-#define foo - ## >> /* { dg-error "pasting \"-\" and \">>\"" } */
+#define foo - ## >> /* { dg-error "pasting '-' and '>>'" } */
foo
-#define bar = ## == /* { dg-error "pasting \"=\" and \"==\"" } */
+#define bar = ## == /* { dg-error "pasting '=' and '=='" } */
bar
Jakub
