diff --git a/.github/workflows/scanbuild_static-analysis.yml b/.github/workflows/scanbuild_static-analysis.yml
index b0fef63006..5c4e149360 100644
--- a/.github/workflows/scanbuild_static-analysis.yml
+++ b/.github/workflows/scanbuild_static-analysis.yml
@@ -25,6 +25,7 @@ jobs:
       run: >
         ./configure
         CFLAGS="-O0 -g"
+        CPPFLAGS="-DMZ_PRECISE_RETURN_SPEC"
         --disable-strip
         --prefix=${{ runner.temp }}/racketcgc
         --enable-werror
@@ -77,6 +78,7 @@ jobs:
       run: >
         ./configure
         CFLAGS="-O0 -g"
+        CPPFLAGS="-DMZ_PRECISE_RETURN_SPEC"
         --disable-strip
         --enable-racket=/usr/bin/racket
         --enable-werror
@@ -133,6 +135,7 @@ jobs:
       run: >
         ./configure
         CFLAGS="-O0 -g"
+        CPPFLAGS="-DMZ_PRECISE_RETURN_SPEC"
         --enable-racket=/usr/bin/racket
         --enable-compress
         --disable-docs