Thanks for the fast answer, sorry if I posted this on the wrong list. Actually I was looking at this not due to changes in my code but rather to implement the option for another compiler and I wanted to mimic the behavior of gcc and was kind of confused in the change of behavior.
Bernhard. Am Di., 29. Jan. 2019 um 10:54 Uhr schrieb David Brown <da...@westcontrol.com>: > > On 28/01/2019 16:58, Bernhard Schommer wrote: > > Hi, > > > > I would like to know if the handling of the option -fno-common has > > changed between version 7.3 and 8.2 for x86. I tried it with the > > default system version of OpenSUSE and for example: > > > > const int i; > > > > is placed in the .bss section. With a newer self-compiled version 8.2 > > the same variable is placed in the section .rodata. I could not find > > any information in the Changelog whether the behavior has changed and > > thus would like to know if there was any change. > > > > (I think this should be on gcc-help, not gcc.) > > "const int i;" is (in C) a tentative definition of an object "i" with > external linkage. If you don't give an initialiser later in the file, > it is equivalent to "const int i = 0;". The compiler knows it cannot > legally change or be anything other than 0, and can therefore put it in > the .rodata section. If you have another "const int i" definition in > another translation unit, you can expect a linker error. > > It seems that gcc 7 put this in .bss. This is equally legal for the > compiler. There should be no difference in how your code works, unless > you are breaking some other C rules along the way. > > > But there is no reason why you should ever write a line "const int i;". > A "const" definition should always have an initialiser - while this > line does the same job as "const int i = 0;" as far as the language is > concerned, it is usually considered better style to initialise const > data explicitly. > > So yes, it looks like the handling of this line has changed between > versions of the compiler. But it should not affect your code functionality. >
