gcc{5,6,7,8}: share libgomp patch, propagate musl config flags

pkgs/development/compilers/gcc/5/default.nix

@@ -60,6 +60,7 @@ let version = "5.5.0";
       ++ optional (targetPlatform != hostPlatform) ../libstdc++-target.patch
       ++ optional noSysDirs ../no-sys-dirs.patch
       ++ optional langFortran ../gfortran-driving.patch
+      ++ optional (targetPlatform.libc == "musl") ../libgomp-dont-force-initial-exec.patch
       ++ optional stdenv.hostPlatform.isMusl (fetchpatch {
         url = https://raw.githubusercontent.com/richfelker/musl-cross-make/e84b1bd1fc12a3def33111ca6df522cd6e5ec361/patches/gcc-5.3.0/0001-musl.diff;
         sha256 = "0pppbf8myi2kjhm3z3479ihn1cm60kycfv60gj8yy1bs0pl1qcfm";
@@ -331,7 +332,12 @@ stdenv.mkDerivation ({
       # On Illumos/Solaris GNU as is preferred
       "--with-gnu-as" "--without-gnu-ld"
     ]
-    ++ optional (targetPlatform == hostPlatform && targetPlatform.libc == "musl") "--disable-libsanitizer"
+    ++ optionals (targetPlatform == hostPlatform && targetPlatform.libc == "musl") [
+      "--disable-libsanitizer"
+      "--disable-symvers"
+      "libat_cv_have_ifunc=no"
+      "--disable-gnu-indirect-function"
+    ]
   ;
 
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;

pkgs/development/compilers/gcc/6/default.nix

@@ -61,6 +61,7 @@ let version = "6.4.0";
       ++ optional langFortran ../gfortran-driving.patch
       ++ [ ../struct-ucontext.patch ../struct-sigaltstack.patch ] # glibc-2.26
       ++ optional langJava [ ../struct-ucontext-libjava.patch ] # glibc-2.26
+      ++ optional (targetPlatform.libc == "musl") ../libgomp-dont-force-initial-exec.patch
       ;
 
     javaEcj = fetchurl {
@@ -336,7 +337,12 @@ stdenv.mkDerivation ({
       # On Illumos/Solaris GNU as is preferred
       "--with-gnu-as" "--without-gnu-ld"
     ]
-    ++ optional (targetPlatform == hostPlatform && targetPlatform.libc == "musl") "--disable-libsanitizer"
+    ++ optionals (targetPlatform == hostPlatform && targetPlatform.libc == "musl") [
+      "--disable-libsanitizer"
+      "--disable-symvers"
+      "libat_cv_have_ifunc=no"
+      "--disable-gnu-indirect-function"
+    ]
   ;
 
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;

pkgs/development/compilers/gcc/7/default.nix

@@ -57,7 +57,7 @@ let version = "7.3.0";
       })
       ++ optional langFortran ../gfortran-driving.patch
       ++ optional (targetPlatform.libc == "musl" && targetPlatform.isPower) ../ppc-musl.patch
-      ++ optional (targetPlatform.libc == "musl") ./libgomp-dont-force-initial-exec.patch;
+      ++ optional (targetPlatform.libc == "musl") ../libgomp-dont-force-initial-exec.patch;
 
     /* Cross-gcc settings (build == host != target) */
     crossMingw = targetPlatform != hostPlatform && targetPlatform.libc == "msvcrt";

pkgs/development/compilers/gcc/8/default.nix

@@ -51,7 +51,8 @@ let version = "8.2.0";
         sha256 = ""; # TODO: uncomment and check hash when available.
       }) */
       ++ optional langFortran ../gfortran-driving.patch
-      ++ optional (targetPlatform.libc == "musl" && targetPlatform.isPower) ../ppc-musl.patch;
+      ++ optional (targetPlatform.libc == "musl" && targetPlatform.isPower) ../ppc-musl.patch
+      ++ optional (targetPlatform.libc == "musl") ../libgomp-dont-force-initial-exec.patch;
 
     /* Cross-gcc settings (build == host != target) */
     crossMingw = targetPlatform != hostPlatform && targetPlatform.libc == "msvcrt";
@@ -284,7 +285,12 @@ stdenv.mkDerivation ({
       # On Illumos/Solaris GNU as is preferred
       "--with-gnu-as" "--without-gnu-ld"
     ]
-    ++ optional (targetPlatform == hostPlatform && targetPlatform.libc == "musl") "--disable-libsanitizer"
+    ++ optionals (targetPlatform == hostPlatform && targetPlatform.libc == "musl") [
+      "--disable-libsanitizer"
+      "--disable-symvers"
+      "libat_cv_have_ifunc=no"
+      "--disable-gnu-indirect-function"
+    ]
   ;
 
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;