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Diffstat (limited to 'include')
| -rw-r--r-- | include/ChangeLog | 4 | ||||
| -rw-r--r-- | include/diagnostics.h | 14 |
2 files changed, 18 insertions, 0 deletions
diff --git a/include/ChangeLog b/include/ChangeLog index e7d6d66..035b3ca 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,7 @@ +2018-07-06 Alan Modra <amodra@gmail.com> + + * diagnostics.h: Comment on macro usage. + 2018-07-05 Simon Marchi <simon.marchi@polymtl.ca> * diagnostics.h (DIAGNOSTIC_IGNORE_DEPRECATED_DECLARATIONS): diff --git a/include/diagnostics.h b/include/diagnostics.h index 34fc01b..9e9d1a8 100644 --- a/include/diagnostics.h +++ b/include/diagnostics.h @@ -16,6 +16,20 @@ #ifndef DIAGNOSTICS_H #define DIAGNOSTICS_H +/* If at all possible, fix the source rather than using these macros + to silence warnings. If you do use these macros be aware that + you'll need to condition their use on particular compiler versions, + which can be done for gcc using ansidecl.h's GCC_VERSION macro. + + gcc versions between 4.2 and 4.6 do not allow pragma control of + diagnostics inside functions, giving a hard error if you try to use + the finer control available with later versions. + gcc prior to 4.2 warns about diagnostic push and pop. + + The other macros have restrictions too, for example gcc-5, gcc-6 + and gcc-7 warn that -Wstringop-truncation is unknown, unless you + also add DIAGNOSTIC_IGNORE ("-Wpragma"). */ + #ifdef __GNUC__ # define DIAGNOSTIC_PUSH _Pragma ("GCC diagnostic push") # define DIAGNOSTIC_POP _Pragma ("GCC diagnostic pop") |