internal/rosa/llvm: exclude runtime symbols

These leak by default when static linking, which is considered unacceptable for many libraries.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/llvm.go

@@ -193,6 +193,10 @@ func init() {
 				"tr",
 				"awk",
 			},
+
+			ScriptEarly: `
+rm -f /system/bin/clang++.cfg
+`,
 		}, &CMakeHelper{
 			Append: []string{"llvm"},
 
@@ -202,7 +206,10 @@ ln -s ld.lld /work/system/bin/ld
 ln -s clang /work/system/bin/cc
 ln -s clang /work/system/bin/cpp
 ln -s clang++ /work/system/bin/c++
-echo '-static-libstdc++' > /work/system/bin/clang++.cfg
+cat << EOF > /work/system/bin/clang++.cfg
+-static-libstdc++
+-Wl,--exclude-libs,libunwind.a:libc++.a:libc++experimental.a:libc++abi.a
+EOF
 `,
 
 			// LLVM_LINK_LLVM_DYLIB causes llvm test suite to leak system

internal/rosa/package/spirv/package.az

@@ -82,7 +82,7 @@ package spirv-llvm-translator {
 	};
 
 	// litArgs emits shell syntax
-	early = "\nexport LIT_OPTS=" + litArgs {
+	early = "rm -f /system/bin/clang++.cfg\nexport LIT_OPTS=" + litArgs {
 		verbose = true;
 
 		skipChecks = arch {