cc-wrapper: Account for NIX_LDFLAGS and NIX_CFLAGS_LINK in linkType

Without this, pkgsStatic.pkgsLLVM.hello fails with segfaulting binaries
because of the issue described at [0].

In summary, llvm's linker has a different behaviour to GCC's when
supplied with both -static and -Wl,-dynamic-linker=...; GCC copes with
it, but LLVM produces a binary which segfaults on startup. It appears to
be necessary to omit the dynamic linker in this case.

nixpkgs' static adaptor passes -static via NIX_CFLAGS_LINK which was not
accounted for prior to this commit in the checkLinkType logic. For good
measure I put the other NIX_ flags affecting link in the same logic.

Additionally, $NIX_CFLAGS_LINK_@suffixSalt@ is not available until later
than it was originally set, so set $linkType close to its point of use.
I checked for earlier uses by studying the shell trace output and
couldn't find any.

[0] https://github.com/NixOS/nixpkgs/issues/111010#issuecomment-1536424163

Signed-off-by: Peter Waller <p@pwaller.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/pkgs/build-support/cc-wrapper/cc-wrapper.sh b/pkgs/build-support/cc-wrapper/cc-wrapper.sh
index 9dcd29c644316..6c43f8cbfa6d2 100644
--- a/pkgs/build-support/cc-wrapper/cc-wrapper.sh
+++ b/pkgs/build-support/cc-wrapper/cc-wrapper.sh
@@ -31,7 +31,6 @@ cxxLibrary=1
 cInclude=1
 
 expandResponseParams "$@"
-linkType=$(checkLinkType "${params[@]}")
 
 declare -ag positionalArgs=()
 declare -i n=0
@@ -175,6 +174,7 @@ extraAfter=(${hardeningCFlagsAfter[@]+"${hardeningCFlagsAfter[@]}"} $NIX_CFLAGS_
 extraBefore=(${hardeningCFlagsBefore[@]+"${hardeningCFlagsBefore[@]}"} $NIX_CFLAGS_COMPILE_BEFORE_@suffixSalt@)
 
 if [ "$dontLink" != 1 ]; then
+    linkType=$(checkLinkType $NIX_LDFLAGS_BEFORE_@suffixSalt@ "${params[@]}" ${NIX_CFLAGS_LINK_@suffixSalt@:-} $NIX_LDFLAGS_@suffixSalt@)
 
     # Add the flags that should only be passed to the compiler when
     # linking.