[PATCH] [libstdc++] [testsuite] avoid arbitrary errno codes

[Alexandre Oliva]

Passing an arbitrary error number to strerror* functions doesn't seem
to be portable; 19_diagnostics/system_error/cons-1.cc is hitting
runtime errors in the block that attempts to instantiate a
std:;system_error for error number 95.  The range of errno macros
defined on this target doesn't reach 95.

I'm changing the test to try to use a couple of select error codes,
falling back to a lower error number if neither are present.
Hopefully this doesn't change the nature of what is being tested for.

Regstrapped on x86_64-linux-gnu, also tested with gcc-13 targeting
aarch64.  Ok to install?


for  libstdc++-v3/ChangeLog

	* testsuite/19_diagnostics/system_error/cons-1.cc: Use lower
	error numbers, preferring some macro-defined ones.
---
 .../19_diagnostics/system_error/cons-1.cc          |   14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/testsuite/19_diagnostics/system_error/cons-1.cc b/libstdc++-v3/testsuite/19_diagnostics/system_error/cons-1.cc
index 16aa960b2ee28..e227c67542411 100644
--- a/libstdc++-v3/testsuite/19_diagnostics/system_error/cons-1.cc
+++ b/libstdc++-v3/testsuite/19_diagnostics/system_error/cons-1.cc
@@ -37,8 +37,18 @@ int main()
 
   // 2
   {
-    std::system_error err2(95, std::system_category(), s);
-    VERIFY( err2.code() == std::error_code(95, std::system_category()) );
+    int eno;
+#if defined EOPNOTSUPP
+    eno = EOPNOTSUPP;
+#elif defined ENOSYS
+    eno = ENOSYS;
+#else
+    // strerror (used to combine with the given message) may fail if
+    // the error number is out of range for the system.
+    eno = 42;
+#endif
+    std::system_error err2(eno, std::system_category(), s);
+    VERIFY( err2.code() == std::error_code(eno, std::system_category()) );
     VERIFY( std::string((err2.what(), s)).find(s) != std::string::npos );
   }
 

-- 
Alexandre Oliva, happy hacker            https://FSFLA.org/blogs/lxo/
   Free Software Activist                   GNU Toolchain Engineer
More tolerance and less prejudice are key for inclusion and diversity
Excluding neuro-others for not behaving ""normal"" is *not* inclusive