[binutils-gdb] gdb/unittests: PR28413, suppress warnings generated by Gnulib

[Simon Marchi <simark@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a5b6e43669b78729d2ef78d668e19bac2b11197d

commit a5b6e43669b78729d2ef78d668e19bac2b11197d
Author: Tsukasa OI <research_trasio@irq.a4lg.com>
Date:   Thu Oct 20 09:32:06 2022 +0000

    gdb/unittests: PR28413, suppress warnings generated by Gnulib
    
    Gnulib generates a warning if the system version of certain functions
    are used (to redirect the developer to use Gnulib version).  It caused a
    compiler error when...
    
    -   Compiled with Clang
    -   -Werror is specified (by default)
    -   C++ standard used by Clang is before C++17 (by default as of 15.0.0)
        when this unit test is activated.
    
    This issue is raised as PR28413.
    
    However, previous proposal to fix this issue (a "fix" to Gnulib):
    <https://lists.gnu.org/archive/html/bug-gnulib/2021-10/msg00003.html>
    was rejected because it ruins the intent of Gnulib warnings.
    
    So, we need a Binutils/GDB-side solution.
    
    This commit tries to address this issue on the GDB side.  We have
    "include/diagnostics.h" to disable certain warnings only when necessary.
    
    This commit suppresses the Gnulib warnings by surrounding entire #include
    block with DIAGNOSTIC_IGNORE_USER_DEFINED_WARNINGS to disable Gnulib-
    generated warnings on all standard C++ header files.
    
    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28413
    Approved-By: Simon Marchi <simon.marchi@efficios.com>
    Change-Id: Ieeb5a31a6902808d4c7263a2868ae19a35e0ccaa

Diff:
---
 gdb/unittests/string_view-selftests.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/gdb/unittests/string_view-selftests.c b/gdb/unittests/string_view-selftests.c
index 2d7261d18d3..86c8f6dc024 100644
--- a/gdb/unittests/string_view-selftests.c
+++ b/gdb/unittests/string_view-selftests.c
@@ -23,6 +23,15 @@
 
 #define GNULIB_NAMESPACE gnulib
 
+#include "diagnostics.h"
+
+/* Since this file uses GNULIB_NAMESPACE, some code defined in headers ends up
+   using system functions rather than gnulib replacements.  This is not really
+   a problem for this test, but it generates some warnings with Clang, silence
+   them.  */
+DIAGNOSTIC_PUSH
+DIAGNOSTIC_IGNORE_USER_DEFINED_WARNINGS
+
 #include "defs.h"
 #include "gdbsupport/selftest.h"
 #include "gdbsupport/gdb_string_view.h"
@@ -34,6 +43,8 @@
 #include <fstream>
 #include <iostream>
 
+DIAGNOSTIC_POP
+
 /* libstdc++'s testsuite uses VERIFY.  */
 #define VERIFY SELF_CHECK