c++visual-studio-2010visual-c++-2010
ceil works without including <cmath> in visual c++ 2010
I just wrote a simple C++ program in Visual Studio 2010 and I use ceil function. But I forgot to include the <cmath> and only included the <iostream>. Surprisingly my code compiled successfully and ran without any error. I read a C++ book and it clearly says that to use ceil function you must include <cmath> or <math.h>. Why this happens? Can anyone explain me? Thanks!
Solution
The header is indirectly included from some other (indirectly) included header.
To find out which one, enable 'keep preprocessed source' (/P) from the project options and inspect the resulting (*.i) file
Update Just found out that VS2010 has renamed the related option:
- Is this declaration UB?
- Calling an external C function (in a shared lib) from Perl with Inline/C does not work
- Eclipse C/C++ how to find variable belongs to which struct quickly
- Is this truly best way to delete last element in C?
- Why do we need address virtualization in an operating system?
- Can a real floating-point type alias a complex floating-point type in C?
- Shadowing an iterator inside a for loop has undefined (?) behaviour in C
- Can a C program execute successfully if main() is defined as a macro?
- Ambiguity in scope of for loop declaration versus body
- Understanding the difference in timing of two functions that increment each element of an integer array
- Why MSVC generates warning C4127 when constant is used in "while" - C
- Executing a user-space function from the kernel space
- Why must the variable used to hold getchar's return value be declared as int?
- mpirun -np 4 ./a.out doesn't use all my cores (ubuntu 24.04LTS)
- Sleep for N seconds and wait for keypress
- Dereference twice in gdb
- Is it safe to cast a struct pointer to a different struct pointer having a prefix of elements?
- Can a C compiler legally reject a program if its call stack depth exceeds a fixed limit at compile time?
- return type defaults to 'int' [-Wimplicit-int]
- What is the scope of `fesetround()`?
- Which specific optimization flag causes libm functions to be treated as pure?
- How to render text in SDL2?
- Why would you use 'extern "C++"'?
- Strange Behavior Compiler Ignoring NULL Check Unless I Print Something in the if Statement
- Fast inverse square root using fixed point instead of floating point
- What is the const qualifier attached to in C: the memory area or the pointer?
- GCC options for strictest C code?
- How to do an explicit fall-through in C
- How do compilers treat CONST qualifier when the pointer points to a memory location obtained with malloc()?
- C: cmocka headers - how to unittest?