From 26547d3e3be403047445fd39e671d7ef3b88dabb Mon Sep 17 00:00:00 2001
From: Lioncash <mathew1800@gmail.com>
Date: Thu, 29 Oct 2020 23:30:42 -0400
Subject: [PATCH] General: Make ignoring a discarded return value an error
Allows our CI to catch more potential bugs. This also removes the
[[nodiscard]] attribute of IOFile's Open member function. There are
cases where a file may want to be opened, but have the status of it
checked at a later time.
---
src/CMakeLists.txt | 6 +++++-
src/common/file_util.h | 2 +-
src/common/misc.cpp | 15 +++++++++++----
3 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 71efbb40d3..29c6ffc678 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -32,7 +32,6 @@ if (MSVC)
# /Zc:inline - Let codegen omit inline functions in object files
# /Zc:throwingNew - Let codegen assume `operator new` (without std::nothrow) will never return null
add_compile_options(
- /W3
/MP
/Zi
/Zo
@@ -43,6 +42,10 @@ if (MSVC)
/Zc:externConstexpr
/Zc:inline
/Zc:throwingNew
+
+ # Warnings
+ /W3
+ /we4834 # Discarding return value of function with 'nodiscard' attribute
)
# /GS- - No stack buffer overflow checks
@@ -56,6 +59,7 @@ else()
-Werror=implicit-fallthrough
-Werror=missing-declarations
-Werror=reorder
+ -Werror=unused-result
-Wextra
-Wmissing-declarations
-Wno-attributes
diff --git a/src/common/file_util.h b/src/common/file_util.h
index 8b587320f2..840cde2a68 100644
--- a/src/common/file_util.h
+++ b/src/common/file_util.h
@@ -232,7 +232,7 @@ public:
void Swap(IOFile& other) noexcept;
- [[nodiscard]] bool Open(const std::string& filename, const char openmode[], int flags = 0);
+ bool Open(const std::string& filename, const char openmode[], int flags = 0);
bool Close();
template <typename T>
diff --git a/src/common/misc.cpp b/src/common/misc.cpp
index 68cb86cd13..1d5393597c 100644
--- a/src/common/misc.cpp
+++ b/src/common/misc.cpp
@@ -16,16 +16,23 @@
// Call directly after the command or use the error num.
// This function might change the error code.
std::string GetLastErrorMsg() {
- static const std::size_t buff_size = 255;
+ static constexpr std::size_t buff_size = 255;
char err_str[buff_size];
#ifdef _WIN32
FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, nullptr, GetLastError(),
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), err_str, buff_size, nullptr);
+ return std::string(err_str, buff_size);
+#elif defined(__GLIBC__) && (_GNU_SOURCE || (_POSIX_C_SOURCE < 200112L && _XOPEN_SOURCE < 600))
+ // Thread safe (GNU-specific)
+ const char* str = strerror_r(errno, err_str, buff_size);
+ return std::string(str);
#else
// Thread safe (XSI-compliant)
- strerror_r(errno, err_str, buff_size);
+ const int success = strerror_r(errno, err_str, buff_size);
+ if (success != 0) {
+ return {};
+ }
+ return std::string(err_str);
#endif
-
- return std::string(err_str, buff_size);
}