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Gcc Error Warning Preprocessor

The specific profiler you use does not really matter, as long as its output can be converted into the format that the LLVM optimizer understands. In many C implementations, it is a separate program invoked by the compiler as the first part of translation. See Line Control. That means that it is possible to use push and pop around GCC compatible diagnostics and Clang will push and pop them appropriately, while GCC will ignore the pushes and pops

De kio “saluton” estas la rekta objekto? However, since the C preprocessor does not have features of some other preprocessors, such as recursive macros, selective expansion according to quoting, string evaluation in conditionals, and Turing completeness, it is See Differences from previous versions. Valid values are: never, optimal and always. https://gcc.gnu.org/onlinedocs/cpp/Diagnostics.html

There are a few more, less useful, features. C compilers and programming environments all have a facility which allows the programmer to define where include files can be found. Preprocessing tokens fall into five broad classes: identifiers, preprocessing numbers, string literals, punctuators, and other.

Pete Goodliffe's Facebook profile What I'm listening to... macro or '#include' recursion too deep #include nested too deeply This error occurs if the preprocessor encounters too many nested '#include' directives. Comments are replaced by whitespace long before stringification happens, so they never appear in stringified text. But what if you want to refer to the old header from the new one?

Furthermore, if you leave the variable argument empty, you will get a syntax error, because there will be an extra comma after the format string. Building a relocatable precompiled header requires two additional arguments. If the new definition is effectively the same, the redefinition is silently ignored. This macro is not defined if the '-traditional-cpp' option is used. __STDC_VERSION__ This macro expands to the C Standard's version number, a long integer constant of the form yyyymmL where yyyy

Common Predefined Macros The common predefined macros are GNU C extensions. There are more fine-grained checks available: see the list of specific kinds of undefined behavior that can be detected and the list of control flow integrity schemes. lprintf ("success!\n", ); --> fprintf (log, "success!\n", ); GNU CPP has a pair of extensions which deal with this problem. Since there are dozens of passes inside the compiler, each of these flags take a regular expression that identifies the name of the pass which should emit the associated diagnostic.

To minimize the risk of different compilers interpreting your computed includes differently, we recommend you use only a single object-like macro which expands to a string constant. https://en.wikipedia.org/wiki/C_preprocessor The front end has a more detailed source location tracking than the locations included in the debug info (e.g., the front end can locate code inside macro expansions). The line may, however, be continued with backslash-newline, or by a block comment which extends past the end of the line. Different systems use different conventions to indicate the end of a line.

Warnings may be set to ignored, warning, error, or fatal. It specifies the operation to perform. The message is actually generated by a #warning directive in the old header files, and not by the preprocessor itself. It searches for a file named file first in the directory containing the current file, then in the same directories used for <file>.

Note that when combined with -w (which disables all warnings), that flag wins. This step feeds the profile back to the optimizers. Exponents are the two-character sequences e+, e-, E+, E-, p+, p-, P+, and P-. (The exponents that begin with p or P are new to C99. Therefore #define HEADER "a\"b" #include HEADER looks for a file named a\"b.

No mean feat! This macro exists primarily to direct GNU libc's header files to restrict their definitions to the minimal set found in the 1989 C standard. __BASE_FILE__ This macro expands to the name The nine trigraphs and their replacements are Trigraph: ??( ??) ??< ??> ??= ??/ ??' ??! ??- Replacement: [ ] { } # \ ^ | ~ Continued lines are merged

For example, in this output, the block containing the callsite of foo was executed 3000 times according to the profile data: s.c:7:10: remark: foo inlined into bar (hotness: 3000) [-Rpass-analysis=inline] sum

It doesn't fail the build with -Werror enabled). This option, which defaults to on, controls whether or not Clang prints the filename, line number and column number of a diagnostic. NOTE: Although the discussion below focuses on -Rpass, the exact same options apply to -Rpass-missed and -Rpass-analysis. Valid values are: arm, thumb and arm,thumb.

If you use the '-Wall' or '-Wtrigraphs' options, GCC will warn you when a trigraph would change the meaning of your program if it were converted. It is destringized, by replacing all ‘ \\ ’ with a single ‘ \ ’ and all ‘ \" ’ with a ‘ " ’. Create a wire coil In the United States is racial, ethnic, or national preference an acceptable hiring practice for departments or companies in some situations? Unlike normal parameter replacement, the argument is not macro-expanded first.

If the filename is enclosed within angle brackets, the file is searched for in the standard compiler include paths. But s is an ordinary argument to xstr, so it is completely macro-expanded before xstr itself is expanded (see Argument Prescan). You can detect problems at compile time and issue errors or warnings. deeply embedded) where a trap cannot be properly handled, or when some custom behavior is desired. -ftls-model=[model]¶ Select which TLS model to use.

There are, however, two ways to make normal headers into system headers. In other words, can I safely use it in my project without breaking the build for compilers that don't support it? If there is white space between a backslash and the end of a line, that is still a continued line. Either the range or the replacement string may be empty (representing strict insertions and strict erasures, respectively).

Valid values are: ieee, preserve-sign, and positive-zero, which correspond to IEEE 754 denormal numbers, the sign of a flushed-to-zero number is preserved in the sign of 0, denormals Object-like macros resemble data objects when used, function-like macros resemble function calls. And it did generate preprocessor errors due to the unknown #warning token. I mean, would it properly generate a warning with other compilers? –aka.nice Jun 11 '13 at 13:34 Just ran a quick check using gcc-4.7.2. [$ gcc -c -Werror file.c]