Linux Eclipse uses the Math library configuration method __linux

Linux, if the program contains MATH.H, you must add LM to GCC for example: Gcc-o main.o main.c-lm
However, compiled under Eclipse, the project automatically generates makefile, which, in any case, modifies the makefile, and is modified by eclipse in its original form at compile time.
This LM is set up in the following way

The online description is as follows:

Select the Tool Settings tab of the drop down menu "settings" for the "project" > "Propertise" > "C + + Build" >c/c++ build >settings > Tool the GCC cllinker option under the Settings tab >GCC the "Libraries" option under the C linker option

At this point, just add a "m" Inside "libraries (L)", when eclipse will generate the-lm parameters of GCC in the makefile that it automatically survives, and then the math function in the MATH.H library will not be able to find it when making the project.

In fact, in the miscellaneous Linker flags to join the-LM can be

The following figure