1 //===-- Definition of a libc internal assert macro --------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #ifndef LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
10 #define LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
11
12 #include "src/__support/macros/config.h"
13 #if defined(LIBC_COPT_USE_C_ASSERT) || !defined(LIBC_FULL_BUILD)
14
15 // The build is configured to just use the public <assert.h> API
16 // for libc's internal assertions.
17
18 #include <assert.h>
19
20 #define LIBC_ASSERT(COND) assert(COND)
21
22 #else // Not LIBC_COPT_USE_C_ASSERT
23
24 #include "src/__support/OSUtil/exit.h"
25 #include "src/__support/OSUtil/io.h"
26 #include "src/__support/integer_to_string.h"
27 #include "src/__support/macros/attributes.h" // For LIBC_INLINE
28 #include "src/__support/macros/optimization.h" // For LIBC_UNLIKELY
29
30 namespace LIBC_NAMESPACE_DECL {
31
32 // This is intended to be removed in a future patch to use a similar design to
33 // below, but it's necessary for the external assert.
report_assertion_failure(const char * assertion,const char * filename,unsigned line,const char * funcname)34 LIBC_INLINE void report_assertion_failure(const char *assertion,
35 const char *filename, unsigned line,
36 const char *funcname) {
37 const IntegerToString<unsigned> line_buffer(line);
38 write_to_stderr(filename);
39 write_to_stderr(":");
40 write_to_stderr(line_buffer.view());
41 write_to_stderr(": Assertion failed: '");
42 write_to_stderr(assertion);
43 write_to_stderr("' in function: '");
44 write_to_stderr(funcname);
45 write_to_stderr("'\n");
46 }
47
48 } // namespace LIBC_NAMESPACE_DECL
49
50 #ifdef LIBC_ASSERT
51 #error "Unexpected: LIBC_ASSERT macro already defined"
52 #endif
53
54 // The public "assert" macro calls abort on failure. Should it be same here?
55 // The libc internal assert can fire from anywhere inside the libc. So, to
56 // avoid potential chicken-and-egg problems, it is simple to do an exit
57 // on assertion failure instead of calling abort. We also don't want to use
58 // __builtin_trap as it could potentially be implemented using illegal
59 // instructions which can be very misleading when debugging.
60 #ifdef NDEBUG
61 #define LIBC_ASSERT(COND) \
62 do { \
63 } while (false)
64 #else
65
66 // Convert __LINE__ to a string using macros. The indirection is necessary
67 // because otherwise it will turn "__LINE__" into a string, not its value. The
68 // value is evaluated in the indirection step.
69 #define __LIBC_MACRO_TO_STR(x) #x
70 #define __LIBC_MACRO_TO_STR_INDIR(y) __LIBC_MACRO_TO_STR(y)
71 #define __LIBC_LINE_STR__ __LIBC_MACRO_TO_STR_INDIR(__LINE__)
72
73 #define LIBC_ASSERT(COND) \
74 do { \
75 if (LIBC_UNLIKELY(!(COND))) { \
76 LIBC_NAMESPACE::write_to_stderr(__FILE__ ":" __LIBC_LINE_STR__ \
77 ": Assertion failed: '" #COND \
78 "' in function: '"); \
79 LIBC_NAMESPACE::write_to_stderr(__PRETTY_FUNCTION__); \
80 LIBC_NAMESPACE::write_to_stderr("'\n"); \
81 LIBC_NAMESPACE::internal::exit(0xFF); \
82 } \
83 } while (false)
84 #endif // NDEBUG
85
86 #endif // LIBC_COPT_USE_C_ASSERT
87
88 #endif // LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
89