## Symbian: separate builds for different S60 editions

Symbian’s build environment was never really my favorite one. Recently I was working on a project using different APIs on S60 3rd, 3rd FP1, 3rd FP2 and 5th editions. Typical Symbian project contains a single `bld.inf` file and a corresponding `.mmp` file, so it is not immediately obvious how to compile conditionally, based on exact S60 release you’re targeting.

I’ve found a solution at Forum Nokia Wiki, but it requires adding a custom file to the SDK, I’m not really happy about it. However a closer look at the build process reveals that `bld.inf` is preprocessed using the following call:

```cpp.EXE -undef -nostdinc -+  -I "C:\Symbian\9.2\S60_3rd_FP1\epoc32\include" -I .
-I "C:\Users\czajnik\work\test\TestApp\group\"  -I "C:\Symbian\9.2\S60_3rd_FP1\epoc32\include\variant"
-include "C:\Symbian\9.2\S60_3rd_FP1\epoc32\include\variant\Symbian_OS_v9.2.hrh"
"C:\Users\czajnik\work\test\TestApp\group\BLD.INF"
```

The most important observation here is the inclusion of `Symbian_OS_v9.2.hrh`. Every SDK release comes with such a file, containing a bunch of `#define` macros denoting features available on a particular platform. With a little help from `grep`, `sort`, `sed` and `diff` I’ve eventually got the following bld.inf file:

```PRJ_PLATFORMS
WINSCW ARMV5 GCCE

PRJ_MMPFILES
gnumakefile Icons_scalable_dc.mk

#ifdef SYMBIAN_C32_SERCOMMS_V2
TestApp_S60_5th.mmp
#else
#ifdef SYMBIAN_APPARC_APPINFO_CACHE
TestApp_S60_3rd_FP2.mmp
#else
#ifdef SYMBIAN_FLEXIBLE_ALARM
TestApp_S60_3rd_FP1.mmp
#else
TestApp_S60_3rd.mmp
#endif
#endif
#endif
```

Works like a charm 🙂