I tried building Rack v2 today, everything looks good (latest v2 git, did the git submodule update, make dep) until I do the make command.
The output is as follows, I am too unfamiliar with it to understand how to fix it 
$ make
cc -Iinclude -Idep/include -fPIC -MMD -MP -g -O3 -march=nocona -funsafe-math-optimizations -Wall -Wextra -Wno-unused-parameter -DARCH_WIN -D_USE_MATH_DEFINES -municode -c -o build/dep/nanovg/src/nanovg.c.o dep/nanovg/src/nanovg.c
In file included from dep/nanovg/src/nanovg.c:26:
dep/nanovg/src/fontstash.h: In function 'fonsAddFont':
dep/nanovg/src/fontstash.h:911:13: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long long unsigned int'} and 'int' [-Wsign-compare]
911 | if (readed != dataSize) goto error;
| ^~
In file included from dep/nanovg/src/nanovg.c:28:
dep/nanovg/src/stb_image.h: In function 'stbi__convert_format':
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1363:10: note: in expansion of macro 'CASE'
1363 | CASE(1,2) dest[0]=src[0], dest[1]=255; break;
| ^~~~
dep/nanovg/src/stb_image.h:1363:49: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1363 | CASE(1,2) dest[0]=src[0], dest[1]=255; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1364:10: note: in expansion of macro 'CASE'
1364 | CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1364:52: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1364 | CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1365:10: note: in expansion of macro 'CASE'
1365 | CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break;
| ^~~~
dep/nanovg/src/stb_image.h:1365:65: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1365 | CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1366:10: note: in expansion of macro 'CASE'
1366 | CASE(2,1) dest[0]=src[0]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1366:36: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1366 | CASE(2,1) dest[0]=src[0]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1367:10: note: in expansion of macro 'CASE'
1367 | CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1367:52: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1367 | CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1368:10: note: in expansion of macro 'CASE'
1368 | CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1368:68: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1368 | CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1369:10: note: in expansion of macro 'CASE'
1369 | CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break;
| ^~~~
dep/nanovg/src/stb_image.h:1369:78: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1369 | CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1370:10: note: in expansion of macro 'CASE'
1370 | CASE(3,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
| ^~~~
dep/nanovg/src/stb_image.h:1370:67: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1370 | CASE(3,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1371:10: note: in expansion of macro 'CASE'
1371 | CASE(3,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = 255; break;
| ^~~~
dep/nanovg/src/stb_image.h:1371:82: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1371 | CASE(3,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = 255; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1372:10: note: in expansion of macro 'CASE'
1372 | CASE(4,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
| ^~~~
dep/nanovg/src/stb_image.h:1372:67: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1372 | CASE(4,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1373:10: note: in expansion of macro 'CASE'
1373 | CASE(4,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1373:85: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1373 | CASE(4,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:1359:44: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
1359 | #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
| ^~~
dep/nanovg/src/stb_image.h:1374:10: note: in expansion of macro 'CASE'
1374 | CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break;
| ^~~~
dep/nanovg/src/stb_image.h:1374:66: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
1374 | CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break;
| ^~~~~
dep/nanovg/src/stb_image.h: In function 'stbi__build_fast_ac':
dep/nanovg/src/stb_image.h:1578:33: warning: left shift of negative value [-Wshift-negative-value]
1578 | if (k < m) k += (-1 << magbits) + 1;
| ^~
dep/nanovg/src/stb_image.h: In function 'stbi__create_png_image_raw':
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4053:13: note: in expansion of macro 'CASE'
4053 | CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); break;
| ^~~~
dep/nanovg/src/stb_image.h:4053:95: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4053 | CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4054:13: note: in expansion of macro 'CASE'
4054 | CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
| ^~~~
dep/nanovg/src/stb_image.h:4054:84: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4054 | CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4055:13: note: in expansion of macro 'CASE'
4055 | CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4055:113: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4055 | CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4056:13: note: in expansion of macro 'CASE'
4056 | CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); break;
| ^~~~
dep/nanovg/src/stb_image.h:4056:139: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4056 | CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4057:13: note: in expansion of macro 'CASE'
4057 | CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4057:102: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4057 | CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4049:17: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4049 | for (k=0; k < nk; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4058:13: note: in expansion of macro 'CASE'
4058 | CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4058:112: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4058 | CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4069:13: note: in expansion of macro 'CASE'
4069 | CASE(STBI__F_none) cur[k] = raw[k]; break;
| ^~~~
dep/nanovg/src/stb_image.h:4069:57: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4069 | CASE(STBI__F_none) cur[k] = raw[k]; break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4070:13: note: in expansion of macro 'CASE'
4070 | CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k-out_n]); break;
| ^~~~
dep/nanovg/src/stb_image.h:4070:88: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4070 | CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k-out_n]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4071:13: note: in expansion of macro 'CASE'
4071 | CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
| ^~~~
dep/nanovg/src/stb_image.h:4071:84: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4071 | CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4072:13: note: in expansion of macro 'CASE'
4072 | CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-out_n])>>1)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4072:106: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4072 | CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-out_n])>>1)); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4073:13: note: in expansion of macro 'CASE'
4073 | CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-out_n],prior[k],prior[k-out_n])); break;
| ^~~~
dep/nanovg/src/stb_image.h:4073:125: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4073 | CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-out_n],prior[k],prior[k-out_n])); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4074:13: note: in expansion of macro 'CASE'
4074 | CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k-out_n] >> 1)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4074:95: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4074 | CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k-out_n] >> 1)); break;
| ^~~~~
dep/nanovg/src/stb_image.h:4067:20: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
4067 | for (k=0; k < img_n; ++k)
| ^~~
dep/nanovg/src/stb_image.h:4075:13: note: in expansion of macro 'CASE'
4075 | CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-out_n],0,0)); break;
| ^~~~
dep/nanovg/src/stb_image.h:4075:105: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
4075 | CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-out_n],0,0)); break;
| ^~~~~
dep/nanovg/src/stb_image.h: In function 'stbi__tga_get_comp':
dep/nanovg/src/stb_image.h:4856:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
4856 | case 16: if(is_grey) return STBI_grey_alpha;
| ^
dep/nanovg/src/stb_image.h:4858:7: note: here
4858 | case 15: if(is_rgb16) *is_rgb16 = 1;
| ^~~~
cc -Iinclude -Idep/include -fPIC -MMD -MP -g -O3 -march=nocona -funsafe-math-optimizations -Wall -Wextra -Wno-unused-parameter -DARCH_WIN -D_USE_MATH_DEFINES -municode -c -o build/dep/osdialog/osdialog.c.o dep/osdialog/osdialog.c
make: *** No rule to make target 'build/dep/oui-blendish/blendish.c.o', needed by 'libRack.dll'. Stop.
(On windows 10 using msys2 mingw 64bit)
I ran into a couple things - I don’t think Rack liked that I was trying to compile in a directory called Rack2. So I renamed the old version Rack 1.0 and once everything was in Rack, and I checked out the v2 branch properly, everything worked fine