diff options
Diffstat (limited to 'target/linux/generic/backport-4.19/012-kbuild-add-macro-for-controlling-warnings-to-linux-c.patch')
| -rw-r--r-- | target/linux/generic/backport-4.19/012-kbuild-add-macro-for-controlling-warnings-to-linux-c.patch | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/target/linux/generic/backport-4.19/012-kbuild-add-macro-for-controlling-warnings-to-linux-c.patch b/target/linux/generic/backport-4.19/012-kbuild-add-macro-for-controlling-warnings-to-linux-c.patch deleted file mode 100644 index 7617c2e5f5..0000000000 --- a/target/linux/generic/backport-4.19/012-kbuild-add-macro-for-controlling-warnings-to-linux-c.patch +++ /dev/null @@ -1,140 +0,0 @@ -From: Arnd Bergmann <arnd@arndb.de> -Date: Tue, 19 Jun 2018 13:14:56 -0700 -Subject: [PATCH] kbuild: add macro for controlling warnings to - linux/compiler.h - -I have occasionally run into a situation where it would make sense to -control a compiler warning from a source file rather than doing so from -a Makefile using the $(cc-disable-warning, ...) or $(cc-option, ...) -helpers. - -The approach here is similar to what glibc uses, using __diag() and -related macros to encapsulate a _Pragma("GCC diagnostic ...") statement -that gets turned into the respective "#pragma GCC diagnostic ..." by -the preprocessor when the macro gets expanded. - -Like glibc, I also have an argument to pass the affected compiler -version, but decided to actually evaluate that one. For now, this -supports GCC_4_6, GCC_4_7, GCC_4_8, GCC_4_9, GCC_5, GCC_6, GCC_7, -GCC_8 and GCC_9. Adding support for CLANG_5 and other interesting -versions is straightforward here. GNU compilers starting with gcc-4.2 -could support it in principle, but "#pragma GCC diagnostic push" -was only added in gcc-4.6, so it seems simpler to not deal with those -at all. The same versions show a large number of warnings already, -so it seems easier to just leave it at that and not do a more -fine-grained control for them. - -The use cases I found so far include: - -- turning off the gcc-8 -Wattribute-alias warning inside of the - SYSCALL_DEFINEx() macro without having to do it globally. - -- Reducing the build time for a simple re-make after a change, - once we move the warnings from ./Makefile and - ./scripts/Makefile.extrawarn into linux/compiler.h - -- More control over the warnings based on other configurations, - using preprocessor syntax instead of Makefile syntax. This should make - it easier for the average developer to understand and change things. - -- Adding an easy way to turn the W=1 option on unconditionally - for a subdirectory or a specific file. This has been requested - by several developers in the past that want to have their subsystems - W=1 clean. - -- Integrating clang better into the build systems. Clang supports - more warnings than GCC, and we probably want to classify them - as default, W=1, W=2 etc, but there are cases in which the - warnings should be classified differently due to excessive false - positives from one or the other compiler. - -- Adding a way to turn the default warnings into errors (e.g. using - a new "make E=0" tag) while not also turning the W=1 warnings into - errors. - -This patch for now just adds the minimal infrastructure in order to -do the first of the list above. As the #pragma GCC diagnostic -takes precedence over command line options, the next step would be -to convert a lot of the individual Makefiles that set nonstandard -options to use __diag() instead. - -[paul.burton@mips.com: - - Rebase atop current master. - - Add __diag_GCC, or more generally __diag_<compiler>, abstraction to - avoid code outside of linux/compiler-gcc.h needing to duplicate - knowledge about different GCC versions. - - Add a comment argument to __diag_{ignore,warn,error} which isn't - used in the expansion of the macros but serves to push people to - document the reason for using them - per feedback from Kees Cook. - - Translate severity to GCC-specific pragmas in linux/compiler-gcc.h - rather than using GCC-specific in linux/compiler_types.h. - - Drop all but GCC 8 macros, since we only need to define macros for - versions that we need to introduce pragmas for, and as of this - series that's just GCC 8. - - Capitalize comments in linux/compiler-gcc.h to match the style of - the rest of the file. - - Line up macro definitions with tabs in linux/compiler-gcc.h.] - -Signed-off-by: Arnd Bergmann <arnd@arndb.de> -Signed-off-by: Paul Burton <paul.burton@mips.com> -Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> -Tested-by: Stafford Horne <shorne@gmail.com> -Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> ---- - ---- a/include/linux/compiler-gcc.h -+++ b/include/linux/compiler-gcc.h -@@ -358,3 +358,28 @@ - * code - */ - #define uninitialized_var(x) x = x -+ -+/* -+ * Turn individual warnings and errors on and off locally, depending -+ * on version. -+ */ -+#define __diag_GCC(version, severity, s) \ -+ __diag_GCC_ ## version(__diag_GCC_ ## severity s) -+ -+/* Severity used in pragma directives */ -+#define __diag_GCC_ignore ignored -+#define __diag_GCC_warn warning -+#define __diag_GCC_error error -+ -+/* Compilers before gcc-4.6 do not understand "#pragma GCC diagnostic push" */ -+#if GCC_VERSION >= 40600 -+#define __diag_str1(s) #s -+#define __diag_str(s) __diag_str1(s) -+#define __diag(s) _Pragma(__diag_str(GCC diagnostic s)) -+#endif -+ -+#if GCC_VERSION >= 80000 -+#define __diag_GCC_8(s) __diag(s) -+#else -+#define __diag_GCC_8(s) -+#endif ---- a/include/linux/compiler_types.h -+++ b/include/linux/compiler_types.h -@@ -283,4 +283,22 @@ struct ftrace_likely_data { - # define __native_word(t) (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) - #endif - -+#ifndef __diag -+#define __diag(string) -+#endif -+ -+#ifndef __diag_GCC -+#define __diag_GCC(version, severity, string) -+#endif -+ -+#define __diag_push() __diag(push) -+#define __diag_pop() __diag(pop) -+ -+#define __diag_ignore(compiler, version, option, comment) \ -+ __diag_ ## compiler(version, ignore, option) -+#define __diag_warn(compiler, version, option, comment) \ -+ __diag_ ## compiler(version, warn, option) -+#define __diag_error(compiler, version, option, comment) \ -+ __diag_ ## compiler(version, error, option) -+ - #endif /* __LINUX_COMPILER_TYPES_H */ |